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 got this error when I had ModalPopupExtender in the update panel... deubbing my code I found that the above error is caused because of updatepanel updatemode is conditional... so i change it to always then problem is solved.