Use connection strings in XRM tooling to connect to Dynamics 365 Customer Engagement (on-premises)

With Dynamics 365 Customer Engagement (on-premises), XRM tooling enables you to connect to your instance by using connection strings. This is similar to the concept of connection strings used with SQL Server. Connection strings have native support in configuration files, including the ability to encrypt the configuration sections for maximum security. This enables you to configure Dynamics 365 Customer Engagement (on-premises) connections at deployment time, and not hard code in your application to connect to your instance.

Note

The connection string documentation that is applicable to Common Data Service users is now available in the Power Apps documentation at: Use connection strings in XRM tooling to connect to Common Data Service

Create a connection string

You specify the connection string in the app.config or web.config file for your project, as shown in the following example.

<connectionStrings>  
    <add name="MyCRMServer" connectionString="AuthType=AD;Url=http://contoso:8080/Test;" />  
</connectionStrings>  

Important

If you add any sensitive information to the app.config or web.config file, for example an account password, be sure to take appropriate security precautions to protect the information.

After creating the connection string, you use it to create a CrmServiceClient object.

//Use the connection string named "MyCRMServer"  
//from the configuration file  
CrmServiceClient crmSvc = new CrmServiceClient(ConfigurationManager.ConnectionStrings["MyCRMServer"].ConnectionString);  

Note

You’ll have to use the following using directive in your code to reference the System.Configuration namespace to access the connection string in your code: using System.Configuration;

After creating a CrmServiceClient object, you can use the object to perform actions in Dynamics 365 Customer Engagement (on-premises). More information: Use XRM Tooling to execute actions

Connection string parameters

The connection string contains a series of name=value pair separated by semi colons. The following table lists supported parameters, which can be entered in any order.

Parameter name Description
ServiceUri, Service Uri, Url, or Server Specifies the URL to the Dynamics 365 Customer Engagement (on-premises) Server. The URL can use http or https protocol, and the port is optional. The default port is 80 for the http protocol and 443 for the https protocol. The server URL is typically in the format of http://crm-server:port/organization-name for Dynamics 365 Customer Engagement (on-premises).

The organization-name is required. You can specify either the friendly or the unique name of the organization to connect to.

Example: http://contoso/test, http://contoso:5555/test, https://contoso/test, or http://10.10.10.2/test.
Domain Specifies the domain that will verify user credentials.
UserName, User Name, UserId, or User Id Specifies the user's identification name associated with the credentials.
Password Specifies the password for the user name associated with the credentials.
HomeRealmUri or Home Realm Uri Specifies the Home Realm Uri.
AuthenticationType or AuthType Specifies the authentication type to connect to Dynamics 365 Customer Engagement (on-premises). Valid values are: AD, IFD (AD FS enabled), OAuth, or Office365.

- AD and IFD are permitted for Dynamics 365 Customer Engagement (on-premises) instances only.
- OAuth, Certificate, and ClientSecret are permitted for Dynamics 365 Customer Engagement (on-premises) and Common Data Service instances. For on-premises, ADFS 3.x+ and App\Client Id registration with ADFS is required for OAuth, Certificate and ClientSecret types.
- Office365 is permitted for Common Data Service instances only.
RequireNewInstance Specifies whether to reuse an existing connection if recalled while the connection is still active. Default value is false that indicates the existing connection be reused. If set to true, will force the system to create a unique connection.
ClientId, AppId or ApplicationId Specifies the ClientID assigned when you registered your application in Azure Active Directory or Active Directory Federation Services (AD FS).

This parameter is applicable only when the authentication type is specified as OAuth.
RedirectUri or ReplyUrl Specifies the redirect URI of the application you registered in Azure Active Directory or Active Directory Federation Services (AD FS).

This parameter is applicable only when the authentication type is specified as OAuth.
TokenCacheStorePath Specifies the full path to the location where the user token cache should be stored. The running process should have access to the specified path. It is the processes responsibility to set and configure this path.

This parameter is applicable only when the authentication type is specified as OAuth.
LoginPrompt Specifies whether the user is prompted for credentials if the credentials are not supplied. Valid values are:

- Always: Always prompts the user to specify credentials.
- Auto: Allows the user to select in the login control interface whether to display the prompt or not.
- Never: Does not prompt the user to specify credentials. If using a connection method does not have a user interface, you should use this value.

This parameter is applicable only when the authentication type is specified as OAuth.
SkipDiscovery Specifies whether to call instance discovery to determine the connection uri for a given instance. As of NuGet release Microsoft.CrmSdk.XrmTooling.CoreAssembly Version 9.0.2.7, default = true. Older versions default to false.
Note: If set to true, it is important that the user provide the correct and accurate URI for the target instance.
Thumbprint or CertificateThumbprint Specifies the thumbprint of the certificate to be utilized during an S2S connection. When set, AppID is required and UserID and Password values are ignored.
StoreName or CertificateStoreName Specifies the store name where the certificate identified by thumbprint can be found. When set, Thumbprint is required.

Note

When using the OAuth AuthType\AuthenticationType
For development and prototyping purposes we have provided the following AppId or ClientId and Redirect URI for use in OAuth Flows.
For production use, you should create an AppId or ClientId that is specific to your tenant in the Azure Management portal.
Sample AppId or ClientId = 51f81489-12ee-4a9e-aaae-a2591f45987d
Sample RedirectUri = app://58145B91-0C36-4500-8554-080854F2AC97

Connection string examples

The following examples show how you can use connection strings for connecting to Dynamics 365 Customer Engagement (on-premises) and IFD deployments. The connection string examples for Common Data Service instances is now available in the Power Apps documentation at: Use connection strings in XRM tooling to connect to Common Data Service

Integrated on-premises authentication

<add name="MyCRMServer"
connectionString="AuthType=AD;
Url=http://contoso:8080/Test;" />  

Named account using on-premises authentication

<add name="MyCRMServer"
connectionString="AuthType=AD;
Url=http://contoso:8080/Test;
Domain=CONTOSO;
Username=jsmith;
Password=passcode" />  

OAuth using named account in Dynamics 365 Customer Engagement (on-premises) with UX to prompt for authentication

Create a new connection using a UserID or Password via oAuth.

Note

OAuth is the preferred auth type for connecting to Dynamics 365 Customer Engagement (on-premises) when using an interactive flow. This auth type fully supports the features of Azure Active Directory Conditional Access and Multi-Factor authentication.

<add name="MyCRMServer"
 connectionString="
  AuthType=OAuth;
  Username=jsmith;
  Password=passcode;
  Url=https://contoso:8080/Test;
  AppId=51f81489-12ee-4a9e-aaae-a2591f45987d;
  RedirectUri=app://58145B91-0C36-4500-8554-080854F2AC97;
  TokenCacheStorePath=c:\MyTokenCache;
  LoginPrompt=Auto"/>  

OAuth using current logged in user with fall back UX to prompt for authentication

Create a new connection using the current logged in user via oAuth.

Note

OAuth is the preferred auth type for connecting to Dynamics 365 Customer Engagement (on-premises) when using a interactive flow. This auth type fully supports the features of Azure Active Directory Conditional Access and Multi-Factor authentication.

<add name="MyCRMServer"
 connectionString="
  AuthType=OAuth;
  Username=jsmith;
  Integrated Security=true;
  Url=https://contoso:8080/Test;
  AppId=51f81489-12ee-4a9e-aaae-a2591f45987d;
  RedirectUri=app://58145B91-0C36-4500-8554-080854F2AC97;
  TokenCacheStorePath=c:\MyTokenCache;
  LoginPrompt=Auto"/>  

Certificate based authentication

Create a new connection to Dynamics 365 Customer Engagement (on-premises) using a Application or Client Id and a Certificate.

<add name="MyCRMServer" 
  connectionString="
  AuthType=Certificate;
  url=https://contoso:8080/Test;
  thumbprint={CertThumbPrintId};
  ClientId={AppId};
  />

ClientId or Client Secret based authentication

Create a new connection to Dynamics 365 Customer Engagement (on-premises) using a Application or Client Id and a Client Secret.

<add name="MyCRMServer" 
  connectionString="
  AuthType=ClientSecret;
  url=https://contoso:8080/Test;
  ClientId={AppId};
  ClientSecret={ClientSecret}
  />

IFD using a named account with delegation to a sub realm

<add name="MyCRMServer"
connectionString="AuthType=IFD;Url=http://contoso:8080/Test;
 HomeRealmUri=https://server-1.server.com/adfs/services/trust/mex/;
Domain=CONTOSO; 
Username=jsmith; 
Password=passcode" />  

Determine your connection status

To determine if the connection request was successful, check the value of the CrmServiceClient.IsReady property. If true, the connection is successful, and you are ready to work. Otherwise, check the values of the CrmServiceClient.LastCrmError and CrmServiceClient.LastCrmException properties for the cause of the connection failure.

See also

Build Windows client applications using the XRM tools
Use CrmServiceClient constructors to connect to Dynamics 365 Customer Engagement (on-premises) and Common Data Service
Use XRM Tooling to execute actions
CrmServiceClient