Reading Pane affects Outlook 2003

[bhaza]

Hello All,
Newbie to the forum - looking for help with Reading Pane issue.
Periodically the Reading Pane (set to Bottom) will appear grayed out and not display a message, telling me to open the item, which does not solve anything - and Outlook will then not allow me to Send or open attachments, etc. and forces me to close/reopen Outlook to clear the problem.

OS: XP SP3
Outlook: Office 2003
Mailbox: kept on Exchange server - not using PSTs except for Archiving

This problem happens with only 1 user. I believe the problem occurs for 2 reasons:


User never closes Outlook.
Keeps many thousands of messages in the Inbox (I read the optimal is to keep it to 5000 or less).

Aside from the obvious practice of lowering the number of messages kept in the Inbox and periodically closing Outlook, any help or insight into this would be greatly appreciated!