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

I have got the same issue, here I give my problem and my solution hoping this would help someone:

Following other people recommendation I went to the log of the server (Windows Server 2012 in my case) in :

Control Panel -> Administrative Tools -> Event Viewer

Then in the left side:

Windows Logs -> Application:

In the warnings I found the message from my site and in my case it was due to a null reference:

*Exception type: NullReferenceException 
Exception message: Object reference not set to an instance of an object.*

And checking at the function described in the log I found a non initialized object and that was it.

So it could be a null reference exception in the code. Hope someone find this useful, greetings.