Outlook calendar

Hi there,
One of my user is having a wierd issue. Everytime that she opens her calendar and the outlook cient is freezed. If she uses the inbox mails then it’s ok. I have tested on multiple machines to ensure that this is not the outlook client cuased it and even reinstalled the outlook client version 2000. It still did not help. I don’t want to blow away her mail box in exchange 5.5 and recreate it. Iam affraid that she would loose her meeting in the calendar. Your tips are much appreciated.
-Thanks inadvanced