The operating system is in debug mode

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at]  

Topic Last Modified: 2005-11-18

The Microsoft® Exchange Server Analyzer Tool queries the Win32_OperatingSystem Microsoft Windows® Management Instrumentation (WMI) class to determine whether a value is set for the Debug property. If the value for this key on an Exchange Server computer is set to True, an error is displayed.

Windows debug mode is toggled by adding the /debug parameter in the Boot.ini file. When /debug is specified in the Boot.ini file of a Windows Server computer, the kernel debugger is loaded during startup and kept in memory at all times. This enables a support professional to dial in to the system being debugged and break in to the debugger, even when the system is not suspended at a Kernel STOP screen. Unlike the /crashdebug switch, the /debug switch uses the COM port whether you are debugging or not. This switch is used when debugging problems that are regularly reproducible. It is likely that the /debug parameter was set as a means to troubleshoot a problem, and was unintentionally left set.

Because of the additional processes that are being run, performance suffers greatly. Therefore, running Exchange Server on a computer where Windows is running in debug mode is not recommended.

To eliminate this error, edit the Boot.ini file and remove the /debug parameter.

To correct this error

  1. In Windows Explorer, navigate to the System Partition. This is the partition that holds the hardware specific files such as Boot.ini and NTLDR.

  2. If you cannot see the Boot.ini file, it could be because the Folder Options are set to Hide protected operating system files. If this is the case, in the Windows Explorer window, click Tools, click Folder Options, and then click View. Clear the Hide protected operating system files (Recommended) check box. When prompted, click Yes.

  3. When the Boot.ini file is visible in Windows Explorer, right-click the file, click Open With, and then select Notepad to open the file.

  4. In the [Operating Systems] section, remove the /debug parameter.

  5. Save and close the file, and then restart the Exchange Server computer for the change to take effect.

For more information about the parameters that can be used in the Boot.ini file, see the Microsoft Knowledge Base article 833721, "Available switch options for the Windows XP and Windows Server 2003 Boot.ini files" (