Troubleshoot Build and Release

Azure Pipelines | Azure DevOps Server 2019 | TFS 2018 | TFS 2017 | TFS 2015

This topic provides general troubleshooting guidance. For specific troubleshooting about .NET Core, see .NET Core troubleshooting.


In Microsoft Team Foundation Server (TFS) 2018 and previous versions, build and release pipelines are called definitions, runs are called builds, service connections are called service endpoints, stages are called environments, and jobs are called phases.

You can use the following troubleshooting sections to help diagnose issues with your pipeline.

My pipeline isn't triggering

If a pipeline doesn't start at all, check the following common trigger related issues.


An additional reason that runs may not start is that your organization goes dormant five minutes after the last user signs out of Azure DevOps. After that, each of your build pipelines will run one more time. For example, while your organization is dormant:

  • A nightly build of code in your organization will run only one night until someone signs in again.
  • CI builds of an Other Git repo will stop running until someone signs in again.

Overridden YAML trigger setting

YAML pipelines can have their trigger and pr trigger settings overridden in the pipeline settings UI. If your trigger or pr triggers don't seem to be firing, check that setting. While editing your pipeline, choose ... and then Triggers.

Pipeline settings UI.

Check the Override the YAML trigger from here setting for the types of trigger (Continuous integration or Pull request validation) available for your repo.

Override YAML trigger from here.

Using pull request triggers with Azure Repos

If your pr trigger isn't firing, and you are using Azure Repos, it is because pr triggers aren't supported for Azure Repos. In Azure Repos Git, branch policies are used to implement pull request build validation. For more information, see Branch policy for pull request validation.

Branch filters in CI and PR triggers

When you define a YAML PR or CI trigger, only branches explicitly configured to be included will trigger a run. Includes are processed first, and then excludes are removed from the list. If you specify an exclude but don't specify any includes, nothing will trigger. For more information, see Triggers.

Scheduled triggers

YAML scheduled triggers are set using UTC time zone. If your scheduled triggers don't seem to be firing at the right time, confirm the conversions between UTC and your local time zone, taking into account the day setting as well.

If your YAML pipeline has both YAML scheduled triggers and UI defined scheduled triggers, only the UI defined scheduled triggers are run. To run the YAML defined scheduled triggers in your YAML pipeline, you must remove the scheduled triggers defined in the pipeline settings UI. Once all UI scheduled triggers are removed, a push must be made in order for the YAML scheduled triggers to start running.

For more information, see Scheduled triggers.

My pipeline tries to start but never gets an agent

If your pipeline tries to start, but never gets an agent, check the following items.

Parallel job limits - no available agents or you have hit your free limits

If you are currently running other pipelines, you may not have any remaining parallel jobs, or you may have hit your free limits.

To check your limits, navigate to Project settings, Parallel jobs.

Pipelines concurrent jobs

You can view the count of in-progress jobs by selecting View in-progress jobs.

View in-progress jobs

You can view all jobs, including queued jobs, by selecting Agent pools from the Project settings.

View queued jobs

In this example, the concurrent job limit is one, with one job running and one queued up. When all agents are busy running jobs, as in this example, the following message is displayed when additional jobs are queued: The agent request is not running because all potential agents are running other requests. Current position in queue: 1. In this example the job is next in the queue so its position is one.

If you are currently running other pipelines, you may not have any remaining parallel jobs, or you may have hit your free limits.

Demands that don't match the capabilities of an agent

If your pipeline has demands that don't meet the capabilities of any of your agents, your pipeline won't start. If only some of your agents have the desired capabilities and they are currently running other pipelines, your pipeline will be stalled until one of those agents becomes available.

To check the capabilities and demands specified for your agents and pipelines, see Capabilities.


Capabilities and demands are typically used only with self-hosted agents. If your pipeline has demands and you are using Microsoft-hosted agents, unless you have explicitly labelled the agents with matching capabilities, your pipelines won't get an agent.

Check Azure DevOps status for a service degradation

Check the Azure DevOps Service Status Portal for any issues that may cause a service degradation, such as increased queue time for agents. For more information, see Azure DevOps Service Status.

My pipeline starts but fails to complete successfully

If your pipeline starts but fails to successfully complete, review the logs to identify the failure and research a solution. Some Common issues and resolutions are provided in the following sections.

Get logs to diagnose problems

Start by looking at the logs in your completed build or release. You can view logs by navigating to the pipeline run summary and selecting the job and task. If a certain task is failing, check the logs for that task.

In addition to viewing logs in the pipeline build summary, you can download complete logs which include additional diagnostic information, and you can configure more verbose logs to assist with your troubleshooting.

Configure verbose logs

To assist with troubleshooting, you can configure your logs to be more verbose.

  • To configure verbose logs for a single run, you can start a new build by choosing Run pipeline (or Queue if you don't have Multi-stage pipelines experience turned on) and selecting Enable system diagnostics, Run.

    Enable system diagnostics

  • To configure verbose logs for all runs, you can add a variable named system.debug and set its value to true.

  • To configure verbose logs for a single run, you can start a new build by choosing Queue build, and setting the value for the system.debug variable to true.
  • To configure verbose logs for all runs, edit the build, navigate to the Variables tab, and add a variable named system.debug, set its value to true, and select to Allow at Queue Time.

View and download logs

To view individual logs for each step, navigate to the build results for the run, and select the job and step.

Task log

To download all logs, navigate to the build results for the run, select ..., and choose Download logs (or Download all logs if you don't have Multi-stage pipelines experience turned on).

Download logs

To download all logs, navigate to the build results for the run, choose Download all logs as zip.

TODO I copied this note from below, what versions does it apply to

Diagnostic logs are not yet available for releases.

In addition to the pipeline diagnostic logs, the following specialized log types are available, and may contain information to help you troubleshoot.

Worker diagnostic logs

You can get the diagnostic log of the completed build that was generated by the worker process on the build agent. Look for the worker log file that has the date and time stamp of your completed build. For example, worker_20160623-192022-utc_6172.log.

Agent diagnostic logs

Agent diagnostic logs provide a record of how the agent was configured and what happened when it ran. Look for the agent log files. For example, agent_20160624-144630-utc.log. There are two kinds of agent log files:

  • The log file generated when you ran config.cmd. This log:

    • Includes this line near the top: Adding Command: configure

    • Shows the configuration choices made.

  • The log file generated when you ran run.cmd. This log:

    • Cannot be opened until the process is terminated.

    • Attempts to connect to your Azure DevOps organization or Team Foundation Server.

    • Shows when each job was run, and how it completed

Both logs show how the agent capabilities were detected and set.

Other logs

Inside the diagnostic logs you will find environment.txt and capabilities.txt.

The environment.txt file has various information about the environment within which your build ran. This includes information like what Tasks are run, whether or not the firewall is enabled, PowerShell version info, and some other items. We continually add to this data to make it more useful.

The capabilities file provides a clean way to see all capabilities installed on the build machine that ran your build.

HTTP trace logs


HTTP traces and trace files can contain passwords and other secrets. Do not post them on a public sites.

Use built-in HTTP tracing

If your agent is version 2.114.0 or newer, you can trace the HTTP traffic headers and write them into the diagnostic log. Set the VSTS_AGENT_HTTPTRACE environment variable before you launch the agent.listener.


    export VSTS_AGENT_HTTPTRACE=true

Use full HTTP tracing - Windows

  1. Start Fiddler.

  2. We recommend you listen only to agent traffic. File > Capture Traffic off (F12)

  3. Enable decrypting HTTPS traffic. Tools > Fiddler Options > HTTPS tab. Decrypt HTTPS traffic

  4. Let the agent know to use the proxy:

  5. Run the agent interactively. If you're running as a service, you can set as the environment variable in control panel for the account the service is running as.

  6. Restart the agent.

Use full HTTP tracing - macOS and Linux

Use Charles Proxy (similar to Fiddler on Windows) to capture the HTTP trace of the agent.

  1. Start Charles Proxy.

  2. Charles: Proxy > Proxy Settings > SSL Tab. Enable. Add URL.

  3. Charles: Proxy > Mac OSX Proxy. Recommend disabling to only see agent traffic.

    export VSTS_HTTP_PROXY=
  4. Run the agent interactively. If it's running as a service, you can set in the .env file. See nix service

  5. Restart the agent.

Common issues and resolutions

My pipeline is failing on a command-line step such as MSBUILD

It is helpful to narrow whether a build or release failure is the result of an Azure Pipelines/TFS product issue (agent or tasks). Build and release failures may also result from external commands.

Check the logs for the exact command-line executed by the failing task. Attempting to run the command locally from the command line may reproduce the issue. It can be helpful to run the command locally from your own machine, and/or log-in to the machine and run the command as the service account.

For example, is the problem happening during the MSBuild part of your build pipeline (for example, are you using either the MSBuild or Visual Studio Build task)? If so, then try running the same MSBuild command on a local machine using the same arguments. If you can reproduce the problem on a local machine, then your next steps are to investigate the MSBuild problem.

Differences between local command prompt and agent

Keep in mind, some differences are in effect when executing a command on a local machine and when a build or release is running on an agent. If the agent is configured to run as a service on Linux, macOS, or Windows, then it is not running within an interactive logged-on session. Without an interactive logged-on session, UI interaction and other limitations exist.

My pipeline is failing on a checkout step

If you are using a checkout step on an Azure Repos Git repository in your organization that is in a different project than your pipeline, ensure that the Limit job authorization scope to current project setting is disabled, or follow the steps in Scoped build identities to ensure that your pipeline has access to the repository.

When your pipeline can't access the repository due to limited job authorization scope, you will receive the error Git fetch failed with exit code 128 and your logs will contain an entry similar to Remote: TF401019: The Git repository with name or identifier <your repo name> does not exist or you do not have permissions for the operation you are attempting.

If your pipeline is failing immediately with Could not find a project that corresponds with the repository, ensure that your project and repository name are correct in the checkout step or the repository resource declaration.

File or folder in use errors

File or folder in use errors are often indicated by error messages such as:

  • Access to the path [...] is denied.
  • The process cannot access the file [...] because it is being used by another process.
  • Access is denied.
  • Can't move [...] to [...]

Troubleshooting steps:

Detect files and folders in use

On Windows, tools like Process Monitor can be to capture a trace of file events under a specific directory. Or, for a snapshot in time, tools like Process Explorer or Handle can be used.

Anti-virus exclusion

Anti-virus software scanning your files can cause file or folder in use errors during a build or release. Adding an anti-virus exclusion for your agent directory and configured "work folder" may help to identify anti-virus software as the interfering process.

MSBuild and /nodeReuse:false

If you invoke MSBuild during your build, make sure to pass the argument /nodeReuse:false (short form /nr:false). Otherwise MSBuild process(es) will remain running after the build completes. The process(es) remain for some time in anticipation of a potential subsequent build.

This feature of MSBuild can interfere with attempts to delete or move a directory - due to a conflict with the working directory of the MSBuild process(es).

The MSBuild and Visual Studio Build tasks already add /nr:false to the arguments passed to MSBuild. However, if you invoke MSBuild from your own script, then you would need to specify the argument.

MSBuild and /maxcpucount:[n]

By default the build tasks such as MSBuild and Visual Studio Build run MSBuild with the /m switch. In some cases this can cause problems such as multiple process file access issues.

Try adding the /m:1 argument to your build tasks to force MSBuild to run only one process at a time.

File-in-use issues may result when leveraging the concurrent-process feature of MSBuild. Not specifying the argument /maxcpucount:[n] (short form /m:[n]) instructs MSBuild to use a single process only. If you are using the MSBuild or Visual Studio Build tasks, you may need to specify "/m:1" to override the "/m" argument that is added by default.

Intermittent or inconsistent MSBuild failures

If you are experiencing intermittent or inconsistent MSBuild failures, try instructing MSBuild to use a single-process only. Intermittent or inconsistent errors may indicate that your target configuration is incompatible with the concurrent-process feature of MSBuild. See MSBuild and /maxcpucount:[n].

Process hang

Process hang causes and troubleshooting steps:

Waiting for Input

A process hang may indicate that a process is waiting for input.

Running the agent from the command line of an interactive logged on session may help to identify whether a process is prompting with a dialog for input.

Running the agent as a service may help to eliminate programs from prompting for input. For example in .NET, programs may rely on the System.Environment.UserInteractive Boolean to determine whether to prompt. When running as a Windows service, the value is false.

Process dump

Analyzing a dump of the process can help to identify what a deadlocked process is waiting on.

WiX project

Building a WiX project when custom MSBuild loggers are enabled, can cause WiX to deadlock waiting on the output stream. Adding the additional MSBuild argument /p:RunWixToolsOutOfProc=true will workaround the issue.

Line endings for multiple platforms

When you run pipelines on multiple platforms, you can sometimes encounter problems with different line endings. Historically, Linux and macOS used linefeed (LF) characters while Windows used a carriage return plus a linefeed (CRLF). Git tries to compensate for the difference by automatically making lines end in LF in the repo but CRLF in the working directory on Windows.

Most Windows tools are fine with LF-only endings, and this automatic behavior can cause more problems than it solves. If you encounter issues based on line endings, we recommend you configure Git to prefer LF everywhere. To do this, add a .gitattributes file to the root of your repository. In that file, add the following line:

* text eol=lf

Variables having ' (single quote) appended

If your pipeline includes a Bash script that sets variables using the ##vso command, you may see an additional ' appended to the value of the variable you set. This occurs because of an interaction with set -x. The solution is to disable set -x temporarily before setting a variable. The Bash syntax for doing that is set +x.

set +x
echo ##vso[task.setvariable variable=MY_VAR]my_value
set -x

Why does this happen?

Many Bash scripts include the set -x command to assist with debugging. Bash will trace exactly what command was executed and echo it to stdout. This will cause the agent to see the ##vso command twice, and the second time, Bash will have added the ' character to the end.

For instance, consider this pipeline:

- bash: |
    set -x
    echo ##vso[task.setvariable variable=MY_VAR]my_value

On stdout, the agent will see two lines:

##vso[task.setvariable variable=MY_VAR]my_value
+ echo '##vso[task.setvariable variable=MY_VAR]my_value'

When the agent sees the first line, MY_VAR will be set to the correct value, "my_value". However, when it sees the second line, the agent will process everything to the end of the line. MY_VAR will be set to "my_value'".

Agent connection issues

Config fails while testing agent connection (on-premises TFS only)

Testing agent connection.
VS30063: You are not authorized to access http://<SERVER>:8080/tfs

If the above error is received while configuring the agent, log on to your TFS machine. Start the Internet Information Services (IIS) manager. Make sure Anonymous Authentication is enabled.

is TFS anonymous authentication enabled

Agent lost communication

This issue is characterized by the error message:

The job has been abandoned because agent did not renew the lock. Ensure agent is running, not sleeping, and has not lost communication with the service.

This error may indicate the agent lost communication with the server for a span of several minutes. Check the following to rule out network or other interruptions on the agent machine:

  • Verify automatic updates are turned off. A machine reboot from an update will cause a build or release to fail with the above error. Apply updates in a controlled fashion to avoid this type of interruption. Before rebooting the agent machine, the agent should first be marked disabled in the pool administration page and let any running build finish.
  • Verify the sleep settings are turned off.
  • If the agent is running on a virtual machine, avoid any live migration or other VM maintenance operation that may severely impact the health of the machine for multiple minutes.
  • If the agent is running on a virtual machine, the same operating-system-update recommendations and sleep-setting recommendations apply to the host machine. And also any other maintenance operations that several impact the host machine.
  • Performance monitor logging or other health metric logging can help to correlate this type of error to constrained resource availability on the agent machine (disk, memory, page file, processor, network).
  • Another way to correlate the error with network problems is to ping a server indefinitely and dump the output to a file, along with timestamps. Use a healthy interval, for example 20 or 30 seconds. If you are using Azure Pipelines, then you would want to ping an internet domain, for example If you are using an on-premises TFS server, then you would want to ping a server on the same network.
  • Verify the network throughput of the machine is adequate. You can perform an online speed test to check the throughput.
  • If you use a proxy, verify the agent is configured to use your proxy. Refer to the agent deployment topic.

Builds or releases not starting

TFS Job Agent not started

This may be characterized by a message in the web console "Waiting for an agent to be requested". Verify the TFSJobAgent (display name: Visual Studio Team Foundation Background Job Agent) Windows service is started.

Misconfigured notification URL (1.x agent version)

This may be characterized by a message in the web console "Waiting for console output from an agent", and the process eventually times out.

A mismatching notification URL may cause the worker to process to fail to connect to the server. See Team Foundation Administration Console, Application Tier. The 1.x agent listens to the message queue using the URL that it was configured with. However, when a job message is pulled from the queue, the worker process uses the notification URL to communicate back to the server.

Team Foundation Version Control (TFVC)

Get sources not downloading some files

This may be characterized by a message in the log "All files up to date" from the tf get command. Verify the built-in service identity has permission to download the sources. Either the identity Project Collection Build Service or Project Build Service will need permission to download the sources, depending on the selected authorization scope on General tab of the build pipeline. In the version control web UI, you can browse the project files at any level of the folder hierarchy and check the security settings.

Get sources through Team Foundation Proxy

The easiest way to configure the agent to get sources through a Team Foundation Proxy is set environment variable TFSPROXY that point to the TFVC proxy server for the agent's run as user.


    set TFSPROXY=http://tfvcproxy:8081
    setx TFSPROXY=http://tfvcproxy:8081 // If the agent service is running as NETWORKSERVICE or any service account you can't easily set user level environment variable


    export TFSPROXY=http://tfvcproxy:8081

Job Time-out

A build or a release may run for a long time and then fail due to job time-out. Job timeout closely depends on the agent being used. Free Microsoft hosted agents have a max timeout of 60 minutes per job for a private repository and 360 minutes for a public repository. To increase the max timeout for a job, you can opt for any of the following.

  • Buy a Microsoft hosted agent which will give you 360 minutes for all jobs, irrespective of the repository used
  • Use a self-hosted agent to rule out any timeout issues due to the agent

Learn more about job timeout.


If your Microsoft-hosted agent jobs are timing out, ensure that you haven't specified a pipeline timeout that is less than the max timeout for a job. To check, see Timeouts.

To troubleshoot issues related to service connections, see Service Connection troubleshooting

Parallel jobs not running

There might be some scenarios where even after purchasing Microsoft-hosted parallel jobs, your runs still sit in the queue and run one after the other. If your jobs aren't running, check the following items.

The following scenarios won't consume a parallel job:

  • If you use release pipelines or multi-stage YAML pipelines, then a run consumes a parallel job only when it's being actively deployed to a stage. While the release is waiting for an approval or a manual intervention, it does not consume a parallel job.
  • When you run a server job or deploy to a deployment group using release pipelines, you don't consume any parallel jobs.

Learn more: How a parallel job is consumed by a pipeline, Approvals within a pipeline, Server jobs, Deployment groups

You don't have enough concurrency

To check how much concurrency you have:

  1. To check your limits, navigate to Project settings, Parallel jobs.

    Concurrent pipeline limits

    You can also reach this page by navigating to{org}/_settings/buildqueue?_a=concurrentJobs, or choosing manage parallel jobs from the logs.

    Manage parallel jobs

  2. Determine which pool you want to check concurrency on (Microsoft hosted or self hosted pools), and choose View in-progress jobs.

  3. You'll see text that says Currently running X/X jobs. If both numbers are the same then jobs will wait until currently running jobs complete.

    View in-progress jobs

Your job may be waiting for approval

Your pipeline may not move to the next stage because it is waiting on approval. For more information, see Define approvals and checks.

All available agents are in use

Jobs may wait if all your agents are currently busy. To check your agents:

  1. Navigate to{org}/_settings/agentpools

  2. Select the agent pool to check, in this example FabrikamPool, and choose Agents.

    Agent status

    This page shows all the agents currently online/offline and in use. You can also add additional agents to the pool from this page.

I need more help. I found a bug. I've got a suggestion. Where do I go?

Get subscription, billing, and technical support

Report any problems on Developer Community.

We welcome your suggestions: