During the profiling of a Silverlight application running in Internet Explorer, ANTS Performance or Memory Profiler may disconnect from the session and start summarizing results. 

This may happen under the following circumstances:

• There is already an instance of iexplore running in the background, and the profiler may attach to that instance. To prevent this, use the Task Manager to check that no instances of iexplore.exe are running.
• Internet Explorer may be in "protected mode" as a result of restarting. Ensure that your IE settings allow it to Run as administrator.
• Javascript in the application may close the web window browser, signalling to the profiler that profiling is complete. 

If all else fails, you may specify the .xap file and profile out-of-browser, if the Silverlight application is configured to run out of browser.