Some months ago a customer of my MZ-Tools add-in reported a crash in Visual Studio 2008 Team Suite when loading it. When an add-in crashes loading it, usually Visual Studio captures the exception or COM error and shows a semi-friendly messagebox indicating that the add-in has caused an exception or failed to load, and give you the chance of removing it. While sometimes the error is <Unknown Error> and you get only the error number (specially if the problem is found by the CLR loading the add-in and not executing the code), this crash was more severe: “Visual Studio needs to close”, and your only options are to close or to restart. MZ-Tools doesn’t have instrumentation yet, but after a couple of custom builds with traces sent to the customer I was able to determine that the problem happened creating the very first toolbar. Somehow the customer changed to Visual Studio 2008 Professional Edition and the problem disappeared so I closed the incident (falsely).

Last week it was a prospect who experienced the severe crash. It is not the best experience for a prospect to download a trial version of your product, install it and get such a crash. I knew that for such severe crashes the problem is not really my add-in but the prospect would think otherwise… Since the add-in is marked to load on startup, it crashes VS every time so chances are that he will uninstall and forget the product. But fortunately he reported it to me, so I troubleshooted it. After a couple of days verifying that the problem was actually MZ-Tools and not other extensions, that the referenced assemblies were present and that the versions were correct, I recalled this problem, that I had almost totally forgotten. I retreived the e-mails of the previous case, and the problem happened with VS 2008 Team Suite also this time. And when I was about to send him a minimal add-in that creates a toolbar to reproduce the problem, I searched the web and I found this post by Jamie Cansdale, former MVP colleague and author of TestDriven.NET (formerly NUnitAddIn):

VS 2008 crashes on startup when ‘Code Analysis Tools’ feature is not installed
http://weblogs.asp.net/nunitaddin/archive/2007/11/29/vs-2008-crashes-on-startup-when-code-analysis-tools-feature-is-not-installed.aspx

So, the problem happens in Visual Studio 2008 Team Suite if you don’t install the “Code Analysis Tools”. Since in the first case the user switched to Visual Studio 2008 Professional Edition, which doesn’t include the Code Analysis Tools (only Visual Studio 2008 Development Edition or Visual Studio 2008 Team Suite), the problem disappeared. In the second case, the prospect run the setup again and certainly the Code Analysis Tools were not installed. After installing them, MZ-Tools loaded fine.

Now, I have tried to reproduce the problem to report it to Microsoft to no avail:

My computer has Visual Studio 2008 Team Suite with the Code Analysis Tools and SP1. I have removed the Code Analysis Tools and the problem doesn’t appear. I have removed the SP1 and nothing. I have removed VS 2008 completely and I have installed it from scratch without the Code Analysis Tools and the problem doesn’t appear. So, I don’t know yet how to reproduce but at least I am glad that I know how to solve it and hopefully I won’t forget it again (I’ll force myself to check the “The strange case of …” series for those rare problems…)

I have also updated this article:

HOWTO: Troubleshooting Visual Studio and Office add-ins
http://www.mztools.com/articles/2007/MZ2007009.aspx

UPDATE (Dec 11, 2008): Finally I have reproduced the problem with a clean virtual machine and Visual Studio 2008 Development Edition without the “Code Analysis Tools” and without installing SP1. The problem happens when an add-in performs certain operations with commandbars of DTE such as:

• Trying to create a toolbar
• Trying to retrieve an nonexistent command bar
• Trying to set the Name property of a Commandbar
• Maybe others

The problem can be solved through two ways:

• Installing the missing “Code Analysis Tools” component
• Installing Service Pack 1

While not many users are affected by this bug since most of them perform a full installation of Visual Studio 2008 and/or install SP1, the problem is so nasty that you may want to detect this circumstance and show a warning when loading your add-in. Something like the following in the OnConnection method before manipulating CommandBars:

If IsVS2008TeamSuite() Or IsVS2008DevelopmentEdition() Then

   If Not IsCodeAnalysisToolsComponentInstalled() Then

      If Not IsVS2008SP1Installed() Then

         MessageBox.Show("This add-in is going to crash :-(")

      End If

   End If

End If

Some details to implement those functions:

• You can detect if VS 2008 SP1 is installed using the registry key:

– HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DevDiv\VSServicing\9.0\VSTS\<locale>, name “SP” for VS 2008 Team Suite

– HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DevDiv\VSServicing\9.0\VSTD<locale>, name “SP” for VS 2008 Development Edition

Where <locale> is the language of Visual Studio, such as 1033 for English, 3082 for Spanish, etc. Your add-in can get the locale of IDE using the DTE.LocaleID property.

The SP value can be 0 (no SP installed) or 1 (SP1 installed).

• You can detect if VS 2008 Team Suite installed if the registry key “HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\9.0\Setup\VS\VSTS” exists.
• You can detect if VS 2008 Development Edition installed if the registry key “HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\9.0\Setup\VS\VSTD” exists.
• You can detect if the “Code Analysis Tools” component is installed getting the folder of VS 2008 (reading the “ProductDir” name under the registry key above), appending “Team ToolsStatic Analysis ToolsFxCop” and checking if the file FxCopSdk.dll exists or not.

Notes:

• VS 2008 without SP1 lacks the folder “Team ToolsStatic Analysis ToolsFxCop” if Code Analysis Tools are not installed (as expected).
• VS 2008 SP1 creates that folder even if you don’t have Code Analysis Tools installed, but it doesn’t add DLLs, just some RepositoryCompatibility folder with some XML files.