Syntax Errors When Emailing External Contacts

The PC I use at work utilises Outllok 2k3, I have it configured so that when I type in the addressees name and 'Ctrl K' outlook looks through my contacts instead of the Global Address List (GAL). Up until last week I had no problems.

Now when I send the email using the above method I receive the following message in the undeliverable report.

A syntax error was detected in the content of the message
The MTS-ID of the original message is: c=GB;a= ;p=mod;l=CTSRSVRMTA1-071031114515Z-23807MSEXCH:MSExchangeMTA:COTTESMORE:CTSRSVRMTA1


This problems only occurs when emailing external contacts and it does not affect all users. If I open a contacts details and then email the contact the message is delivered. If I reconfigure outlook to look through the GAL first and then I select the addressee the email is delivered.

The problem only occurs when outlook is set to check names in the contacts address list and when the addressee is an external contact i.e not on the same site. The problem also occurs on whatever machine i log on to and is not specific to one machine.

I have created a new profile which did not help, I also created a new mailbox and this did not help. The problem, as I see it, is when adding an external contact using 'Ctrl K'.

Can you offer any advice?

Regards

Paul

 

Anyone got any ideas?