Getting the Sys.WebForms.PageRequestManagerParserErrorException while making an AJAX callback

Recently I encountered an issue wherein our customer was running into a client side AJAX exception, Sys.WebForms.PageRequestManagerParserErrorException, while trying to make an Async Postback from an ASPX page. This exception was happening for all the clients in a specific network and looked like this: ————————— Microsoft Internet Explorer ————————— Sys.WebForms.PageRequestManagerParserErrorException: The message received from the…


“Parser Error Message: This implementation is not part of the Windows Platform FIPS validated cryptographic algorithms.” when .net page has debug=”true”

Recently, I came across an issue where the customer faced an FIPS (Federal Information Processing Standards) related error on the .aspx pages which had debug=”true”. His application was hosted on IIS7 running on Windows Server 2008 SP2.  And, he was able to reproduce the issue using a very simple page. The error message was:…


HttpException Due to Invalid Viewstate After Installing .NET Framework 3.5 SP1

In the recent past I have come across several issues where our customers have started running into ViewState issues after installing SP1 for .NET Framework 3.5. The exception details are similar to the following:   Server Error in ‘/ActionTest’ Application. Validation of viewstate MAC failed. If this application is hosted by a Web Farm or…


<location> Tag Causes Local Automatic ASP.NET debugging not to work in Visual Studio

This week I got an interesting issue altogether. One of my customers was unable to debug ASP.NET 3.5 application locally using Visual Studio 2008. The application was created using Web Application Project. When we started the application using "Start Debugging (F5)", page came up fine but debugger was not getting attached to process. In Visual…


Weeking recap of ASP.NET Debugging blog

Here are last weeks updates to the ASP.NET Debugging blog: Code Gallery and CodePlex, how are they different and what are their benefits? An Open Debugger Extension Job openings with the .NET Framework Team ASP.NET Tips- What to gather to troubleshoot – part 1 – High CPU

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