To enable IDE Integration in Visual Basic and Visual C++:
To disable IDE Integration, uncheck the box.
The default setting is unchecked.
The “Express” versions of Visual Studio do not support source control integration and enabling this option does not override these limitations.
You can select Vault Professional Classic Client IDE Integration in Visual Studio 2005 and later by clicking Tools->Options->Source Control->Plugin Selection and selecting SourceGear Vault Professional Classic Client for the current source control plugin.