I get these annoying message on w Windows 2003 Server with Exchange Installed, when trying to do mail merge or send do as attachement from within Word:

 

"mapi32.dll is an invalid Extended MAPI Library
Mail is not installed on your system"

 

I looked everywhere how to fix it, but it turns out there's a really easy fix for it.

 

From the TomorrowMan:

"This appears to be because the Exchange 2003 version of mapi32.dll located in c:\windows\system32\ has overwritten the Office 2003 version of MAPI32.dll and they are different.

To fix this problem I just took a copy of mapi32.dll from another Office 2003 installation and placed it in C:\Program Files\Microsoft Office\OFFICE11\ because it seems office will look there first, and voila it now works. "

Works like a charm.