Check for third party software interference
If you have tried activating and reactivating as well as reinstalling and LetterMark still does not show up in the Outlook client. Please be sure you do not have any devices or programs running Outlook in the background in a hidden state (look in the task manager process list to see if outlook.exe is running) If Outlook is running and not showing up, when you start Outlook, from the start menu or the icon, LetterMark will most likely not load. You will need to make sure that Outlook is NOT running in the background. Calendar Syncing applications and PDAs will start Outlook but not display a window and this will interfere with LetterMark. If all of this has been done please let us know and we can provide still more troubleshooting options.