Dr. Watson Fails to Appear When Applications Fail Because of Long File Names in Path

Applications that are running on a computer running Windows NT Server or Windows NT Workstation may fail, but there is no error message or any other indication of failure, and no log is ever created.

During the installation of certain applications such as Visual C++ 5.0, the setup program changes the default debugger to the application itself. If that application is installed in a location that contains a long file name, or spaces in the path, the previously described symptom occurs.

Use one of the following methods to resolve this problem. The first two methods change the default debugger back to Dr. Watson.

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it.

Method 1

1. Click Start, point to Programs, and then click Command Prompt.
2. Type the following command to start Dr. Watson and change Dr. Watson to the default debugger:
   
   Drwtsn32 -i

Method 2

1. Run Registry Editor (regedt32.exe).
2. Go to the following key:
   HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\CurrentVersion \AeDebug
   
   NOTE: The above registry key is one path; it has been wrapped for readability.
3. To change the default debugger back to Dr. Watson, modify the debugger value to the following:
   Value Name: Debugger Data Type : REG_SZ Data : Drwtsn32 -p %ld -e %ld

Method 3

The following method will allow Visual C++ 5.0 to run as the default debugger:

1. Run Registry Editor (regedt32.exe).
2. Go to the following key:
   HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\CurrentVersion \AeDeb
   
   NOTE: The above registry key is one path; it has been wrapped for readability.
3. Modify the current debugger path to use the short file name, or place quotation marks around the data path to allow the spaces to be correctly interpreted.
   
   For example, if Visual C++ 5.0 is installed and the path is C:\Program Files\<application>, change the data value to the following:
   Value Name: Debugger Data Type : REG_SZ Data : C:\Progra~1\DevStudio\SharedIDE\Bin\Msdev.exe %ld -e %ld
   
   -or-
   Data : "C:\Program Files\DevStudio\SharedIDE\Bin\Msdev.exe %ld -e %ld"
   
   NOTE: The above registry key is one path; it has been wrapped for readability.

Microsoft has confirmed this to be a problem in Windows NT version 4.0. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

When an application fails on a computer running Windows NT, that application tries to load a specified debugger, to log information about the failure. Windows NT attaches the specified debugger to the application, and generates a log will that contains information about the cause of the application failure. By default, Windows NT launches Dr. Watson. However, certain applications may change this default and include the path to the new debugger.

If the path includes a long file name such as:



Windows NT will not read the path correctly, and the debugger for an application that is failing will not load unless the full path is specified in the user's environment.