If you have trouble integrating applications with GroupWise MAPI, try the workaround described in the following sections.
When gwmailto.exe is registered, it intercepts the following three simple MAPI functions:
If you use MAPILogon, gwmailto.exe returns an invalid MAPI session handle. Any applications that call MAPILogon while gwmailto.exe is registered as the default mail client cannot call extended MAPI features.
To workaround this issue, use one of the following two workarounds:
Because MAPILogonEx is not intercepted by gwmailto, MAPILogonEx is processed through the normal route of the message store provides that is configured in the MAPI profile.
IMPORTANT:Uninstalling gwmailto prevents any “mailto:” links from working correctly in your Internet browser.