I recently had to install Visual Studio 2005 on a Windows 8. The solution used WSE 3.0, so I need to install the WSE tools.
It turns out the add-in doesn't get installed into Visual Studio 2005 properly.
I found that I had to manually tell Visual Studio to look for the add-in in another folder.
- Go to Tools -> Options -> Environment -> Add-in/Macros Security
- In the Add-in File Paths list, add the following path: