MS Outlook is in itself already a very annoying and not very pleasant piece of software. But sometimes you have to use it, no matter what. I will live.
But running again and again into the problem that Outlook conveniently forgets the correct calendar view really became a problem. Especially when it happens to everybody and they come to me to fix it.
At least it is easy to fix, but let me describe the problem first. It happens quite frequently that Outlook simply forgets the saved calender view. In our case that was usually the monthly view. It happens when you run a filter on your calendar. Outlook assumes the filtered view to be the new default. Well, that is just wrong.
Depending on the version of Outlook you have to perform one of the following steps.
Outlook 2007
Menu bar > View > Arrange By > Current View > Day/Week/Month
Outlook 2010
Menu bar > View > Change View > Manage Views > Select view name "Calendar" in the list Click "Apply View"