Does anyone know of a way to close Outlook via a VB program?

I wrote a clumsy program which opens Outlook and sends keys to exit and log off, but there are too many situation the sendkeys routine doesn't work. I am looking at backup solutions for our company and one of the big problems is most backup programs cannot back up open files. Outlook's .pst files are the most important files for us to be able to back up but if a user leaves Outlook open, the .pst file won't be backed up.

Any help would be appreciated.

Thanks,

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