Most Common ASP.NET Support issues

Below is a summary of the “two top things that cause trouble in production ASP.NET web sites,” per Scott Hanselman, which he obtained from deep within Microsoft Developer Support.  Go here to read the complete article.

#1 Issue – Configuration

Seems the #1 issue in support for problems with ASP.NET 2.x and 3.x is configuration. 

Symptoms Notes
High memory
There are more debug=true cases than there should be.


#2 Issue – Problems with an External (non-ASP.NET) Root Cause

Sometimes when you’re having trouble with an ASP.NET site, the problem turns out to not be ASP.NET itself.

Issue Product Description Symptoms Notes
Anti-virus software All Anti-virus software is installed onto Servers and causes all kinds of problems.
  • Application restarting
  • Slow performance
  • Session variable are null
  • Cannot install hotfix
  • Intermittent time outs
  • High memory
  • Session lost
  • IDE Hangs
  • Deadlocks

This consists of all AV software reported by our customers. All cases do not report the AV software that is being used so the manufacturer is not always known.

KB821438, KB248013, KB295375, KB817442

3rd party Vendors All This is a category of cases where the failure was due to a 3rd party manufacturer.
  • Crash
  • 100% CPU
  • High memory
  • Framework errors
  • Hang
The top culprits are 3rd party database systems, and 3rd party internet access management systems
Microsoft component All Microsoft software
  • Intermittent time outs
  • High memory
  • Deadlocks
  • 100% CPU
Design issues that cause performance issues like sprocs, deadlocks, etc. Profile your applications and the database! (Pro tip: select * from authors doesn’t scale.) Pair up DBAs and programmers and profile from end to end

How-to: Unable to cast object Microsoft VisualStudio TestTools UnitTesting TestConfiguration

I was getting this error when running one of my unit tests:

Unit Test Adapter threw exception: The type initializer for ‘Microsoft.VisualStudio.TestTools.UnitTesting.TestConfiguration’ threw an exception.
Unable to cast object of type ‘Microsoft.VisualStudio.TestTools.UnitTesting.TestConfigurationSection’ to type ‘Microsoft.VisualStudio.TestTools.UnitTesting.TestConfigurationSection’.

The issue was due to a versioning problem in the .config file (I upgraded to VS 2008).  The section that you’ll want to change is Version= to Version=

<section name=”microsoft.visualstudio.testtools” type=”Microsoft.VisualStudio.TestTools.UnitTesting.TestConfigurationSection, Microsoft.VisualStudio.QualityTools.UnitTestFramework, Version=, Culture=neutral, PublicKeyToken=…”/>

Hope this helps.