ASP.NET Ajax Error: Sys.WebForms.PageRequestManagerParserErrorException

Question

My website has been giving me intermittent errors when trying to perform any Ajax activities. The message I get is

Sys.WebForms.PageRequestManagerP         


        

Answer 1

This may be a little hacky, but it solved the issue for me. I didn't have any of the common reasons for the error, so I just put in this band-aid in the page load:

if (Session.SessionID == "")
{
    Page.Session.Add("SessionID", Session.SessionID);
}