Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occurred while processing the request on the server."

Question

I have couple of update panels and jquery tabs on page. And also I am loading couple user controls on update panels. After user waited for couple of minutes (not checked the

Answer 1

For those using the internal IIS of Visual Studio, try the following:

1. Generate the error message.
2. Break the debugger at the error display.
3. Check the callstack. You should see 'raise'.
4. Double click 'raise'.
5. Check the internals of 'sender' parameter. You will see a '_xmlHttpRequest' property.
6. Open the '_xmlHttpRequest' property, and you'll see a 'response' property.
7. The 'response' property will have the actual message.

I hope this helps someone out there!