User is not receiving Outlook calendar reminder alerts

Hi,

I have a very unusual issue with a user where they have stopped receiving Outlook Calendar reminder notification window that they can click "snooze" on for their appointments and meetings.

I have tried a few things to fix this:

- Migrate user to our Exchange 2010 SP1 Server (we are in the process of migrating everyone) and discard any corrupt items.
- Starting Outlook.exe with every /switch
- Creating a new windows profile for user, on a new computer and testing it on there, no popup reminders.
- Turning reminder setting in outlook off and then on

I am stuck as to what else to do next, it is only happening to this one user in our 300 user environment.

Any ideas as to what to do next?

I don't think this is an issue on the clients machine, as I have an identical profile/outlook setup under their account, and can't get their calendar alerts to show up.