I recently heard from a customer who tried to install Visual Studio 2005 SP1, but the installation was blocked with a message stating that the Visual Studio 2005 Web Application Project add-in needed to be uninstalled first. However, the system did not have any items with that name in the Add/Remove Programs list.
Microsoft released a new set of web application projects for Visual Studio 2005 after the final release of Visual Studio 2005, and they are now included as a part of VS 2005 SP1. Because they are included in SP1, the standalone version must be uninstalled before installing SP1. The tricky thing here is that there are 2 programs that have to be removed to fully uninstall the web application project add-in from Visual Studio 2005 to allow installing SP1 - the MSI-based add-in, and a Visual Studio 2005 hotfix to support web application projects.
If you have the Visual Studio 2005 Web Application Project add-in installed and want to be able to install Visual Studio 2005 SP1, you can use the following steps to uninstall both of the programs that must be uninstalled:
- Click on the Start menu, choose Run, type appwiz.cpl and click OK
- In the Add/Remove Programs control panel, locate and remove the item named Microsoft Visual Studio 2005 Web Application Projects
- Check the box named Show updates at the top of the Add/Remove Programs control panel
- Under Microsoft Visual Studio 2005, locate the update named Update for Microsoft Visual Studio 2005 (KB915364) and choose to uninstall it
After uninstalling both of the above packages, you should no longer receive a blocking dialog related to the Web Application Project add-in when trying to install VS 2005 SP1.