This problem can be identified by examining the log files.
The log files: MsgSave.log and MsgSave2.log are stored here:

Vista/Windows 7: C:\Users\username\AppData\Roaming\Sarcophagus Ltd\MsgSave\
Or C:\Users\username\AppData\Local\Sarcophagus Ltd\MsgSave\
XP: C:\Documents and Settings\username\Application Data\Sarcophagus Ltd\MsgSave\

If there is an exception thrown in the callback function for the registration webservice and the inner exception contains html with a title of: Object moved.

This appears to be caused by internet access being blocked by another Outlook add-in called collaboration.

In order to resolve this issue remove the collaboration add-in.