If you've tried (for example) installing Visual Studio 2005 on Longhorn you may have found that it did not install correctly (right Mauricio?)
If this is you - or you've found another bug in Visual Studio 2005, you can report it using our online tools.
Have you got an idea for Visual Studio 2005 that would make it better? You cal also suggest it!
You can report bugs and suggestions as well as see a list of existing bugs and suggestions at http://lab.msdn.microsoft.com/vs2005/ - Look for Product Feedback Center on the right side of the page under the blue express editions buttons.