Today I was trying to edit a .NET 3.0 Workflow application for Sharepoint which someone else had written. I have just recently installed Visual Studio 2005 with Service Pack 1 and all the add on packs, HOWEVER whenever I tried to open this particular .csproj file on my PC I kept getting the following error in Visual Studio:

"The project type is not supported by this installation"

After searching around google and the only half shot was from a forum suggesting doing a 'devenv /setup' at the Visual Studio Command prompt (which didn’t work), I thought it was time to get my hands dirty and have a look at the XML in the .csproj file for the project. One particular element I noticed which wasn't in the other .csproj files was the following:

<ProjectTypeGuids>{14822709-B5A1-4724-98CA-57A101D1B079};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>

As soon as I removed this node from my project file, then reopened it, I got a new error. This referenced "Microsoft\Windows Workflow Foundation\v3.0\Workflow.Targets" as the cause of the error. A spot of googling discovered that these files are used tools for Windows Workflow, which is in fact the not so easy to find "Visual Studio 2005 extensions for .NET Framework 3.0 (Windows Workflow Foundation)" (download

I installed this and got all excited that I was giong to be able to start cutting code. Wrong. I was now getting a new message:

Oh and there was no link (I hate it when you are referenced a particular prerequisite and there is no link to easily go and add the missing component).

Back to google for another search around and I realised that the machine I was using did NOT in fact have .NET 3.0 installed. So I got the download 

Moral of the story: If you are trying to develop with .NET 3.0 maybe it’s a good idea to check that .NET 3.0 is installed first...