A. XP has an MSN Service client built in; however, the built-in client doesn't support Exchange messaging, and it's a newer version than the Exchange MSN Messenger Service client on Microsoft's Web site. Thus, if you try to install the Exchange MSN Messenger Service client, the system won't let you because a more recent version is already installed.
To work around this problem, you need to delete the MSN Messenger folder from the XP machine; you can then install the Exchange MSN client.
- Start Windows Explorer.
- Go to the folder %SystemDrive%:\Program Files\Messenger.
- Ensure that MSN Messenger isn't running—its icon shouldn't appear in the system tray. If it is running, right-click the icon and select Exit.
- Rename the Messenger folder.
- Run mmssetup.exe.
- When the installation is complete and you're sure it works, delete the old Messenger folder.
An alternative is to simply install an extra MSN Messenger directly into a folder but don't run the install:
mmssetup /c /t:\[location of Messenger\]For example,
mmssetup /c /t:"c:\program files\Messenger".