Sys.WebForms.PageRequestManagerParserErrorException
Raised by the PageRequestManager class when there is an error processing the response to an asynchronous postback.
Remarks
When an error occurs on the server while processing the response to an asynchronous postback, a PageRequestManagerParserErrorException object is created by using the Error.create function. For information about how to handle this error condition, see Debugging and Tracing Ajax Applications Overview.