Outlook 2010 freezes while trying to open archive items

Hi All,

One of my user is having issue once he open archive items in Outlook. Outlook freezes for arround 10-20minutes and sometimes need to close then re-open outlook. User is having an issue when his mailbox is in Exchange 2003 and EV 8. He still encounters the issue after his mailbox was migrated to Exchange 2010 SP3 RU4 and EV 10.0.4

We've tried to set his account on other computer but same issue was encountered. By the way, the issue is not happening all the time. It is just intermittent.

Hope someone could help us on this.