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 had the same issue, when i was trying out a way to solve it, i found out that the update panel was causing this issue. Depending on my requirement i could remove the update panel and get rid of the issue. So it's a possible solution for the issue.

Answer 2

This is not the real problem, if you want to see why this is happening then please go to error log file of IIS.

in case of visual studio kindly navigate to:

C:\Users\User\Documents\IISExpress\TraceLogFiles\[your project name]\.

arrange file here in datewise descending and then open very first file.

it will look like:

now scroll down to bottom to see the GENERAL_RESPONSE_ENTITY_BUFFER it is the actual problem. now solve it the above problem will solve automatically.

Answer 3

I had this issue and I spent hours trying to fix it.

The solution ticked as answered will not fix the error only handle it.

The best approach is to check the IIS log files and the error should be there. It appears that the update panel encapsulates the real error and outputs it as a 'javascript error'.

For instance my error was that I forgot to make a class [Serializable]. Although this worked fine locally it did not work when deployed on the server.

Answer 4

This issue for me was caused by a database mapping error.

I attempted to use a select() call on a datasource with errors in the code behind. My controls were within an update panel and the actual cause was hidden.

Usually, if you can temporarily remove the update panel, asp.net will return a more useful error message.

Answer 5

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!

Answer 6

We also faced the same issue, and the problem could only be reproduced in the server (i.e., not locally, which made it even harder to fix, because we could not debug the application), and when using IE. We had a page with an update panel, and within this update panel a modalpopupextender, which also contained an update panel. After trying several solutions that did not work, we fix it by replacing every imagebutton within the modalpopupextender with a linkbutton, and within it the image needed.