Emails do not end up in Outlook Sent Items folder

[yahya]

Hi

Blackberry 8310 Curve on an Microsoft Small Business Server 2003
Network (MS Exchange 2003). The user’s client win xp pc uses Blackberry
Desktop Software 4.7.

The supplier is Vodafone and on Vodafone/Blackberry site the user
account is set to send/received via MS Exchange Remote Outlook Access.

All worked well till a few days ago, since then any emails that are
replied from the Blackberry device get a cross (X) in the Blackberry but
do seem to be sent. The second problem is that the sent emails do not
appear in user’s Outlook Sent Items folder.

What is the problem and how can I fix it?

Thanks

Regards