If your application is running partially and no longer in a stable state suitable for testing. Then
1. Reboot your system (or reinstall a clean image of the build) and attempt to reproduce the issue,
paying particular attention to the steps required to get there.
2. Document your findings in a defect report. Don't forget to include screen shot(s). If error messages
are returned by the application during failure, include this in your report.
3. If you want to determine the source of the existing defect, then check the Error Logs on the local and/or serving computers. The error messages in these logs will often describe the nature and source of the problem.
4. Testers can set the Event Filter of this log if they know the event type or session they wish to examine. Event Details provides an exception stack trace that can be included in the defect report.