Outlook asks for credentials

Hi Experts,

Hope i can make myself clear on this one. I've got the following problem;

In the network there are 2 Windows 7 x64 pc's with Outlook 2010 e-mail cliënt. Server is Exchange 2010 SP1. These pc's are just there to receive e-mail messages from customers. The messages contain pdf documents.

I've configured some sort of mailflow on the Exchange server.

1. Customers can send their messages to 2 different e-mail addresses.
2. These 2 addresses are configured to forward the messages to a single address.
3. This single address is configured on PC1.
4. On PC1 there is a script running, thats pulls the attachement out of the e-mail, and copy
     it to a network share.
5. The script is triggered by a rule created in Outlook.

PC2 has about the same configuration as PC1. It has a different account configured in Outlook. Mail from 8 e-mailadresses are forwarded to the address configured on PC2.

Users logon to the pc's using rdp once in a while to check if everything is running well. PC2 is Always running without problems. On PC2 however, there are problems every single day.

In Outlook, where it usually says 'connected to Exchange' it says 'credentials required'. The rules configured to fire up the scripts turn red and say ERROR. After a reboor everything works fine.


Any help to fix this problem is more then welcome....