On a computer that is running the 64-bit version of Windows Vista or the 64-bit version Windows Server 2003, no more than 1,024 methods can be present in one COM interface.

This limitation makes some applications that have more than 1,024 methods, such as Microsoft Project (WinProj.exe), unable to contain more methods.

When you use a Component Object Model (COM) add-in to change programs that are installed on a Windows Vista-based computer, the changes may take longer than you expect to be completed.