Restart your computer and try again.
If it's still happening please post the complete error message.

You can try repairing your Microsoft Suite.

Depending on your OS you will need to go to add/remove programs and find Microsoft Office, click change and click repair.

This could be the result of a virus, have you tried running a scan or do you have realtime AV running? Also Microsoft as acknowledged that it may also be a printer incompatibility.

A complete error would be nice as it would be easier to see exactly what's going on!