When the Microsoft Online Services Sign-in Assistant service is running, you can't rename or delete the debug trace because the file is being used by a process. The names of the trace files are in the following format: On drive C, locate the MSOTrace and MSOTraceLite folders. Reproduce the suspected authentication issue on the computer on which tracing is enabled. Open an administrative command prompt, and then run the following commands (press Enter after each command): net stop msoidsvc Right-click the Microsoft Online Services Sign-in Assistant service, and then select Restart. Select Start, type services.msc in the search box, and then press Enter. To restart the Microsoft Online Services Sign-in Assistant service, do one of the following: If the Microsoft Online Services Sign-in Assistant service isn't installed on your system, go to step 4. The Microsoft Online Services Sign-in Assistant service is required to be installed only on systems that are running pre-Office 2013 versions of Office or on systems that use PowerShell to connect to Office 365. Restart the Microsoft Online Services Sign-in Assistant service (if it's installed). Run the Enable_SIA_Debug_Tracing.reg file on the computer that's experiencing the issue to update the registry. Start Notepad, copy and paste the following text to a new file, and then save the file as Enable_SIA_Debug_Tracing.reg: Windows Registry Editor Version 5.00 To enable debug tracing for the Microsoft Online Services Sign-in Assistant, follow these steps: Enable debug tracing for the Microsoft Online Services Sign-in Assistant Before you modify it, back up the registry for restoration in case problems occur.

Serious problems might occur if you modify the registry incorrectly. Follow the steps in this section carefully.

Microsoft account sign in assistant