Thanks for your wisdon so far... to answer the points raised:

The service account

the service account I got set up is a domain account with access to all the network resouces required including the mailbox I want to monitor - I've even given it local admin rights on the workstation(s) to no avail

MAPI/Exhange Profiles

I'd thought of that... if I actually log on interactively as the service account everything works. I created an Outlook profile in Control Panel but it works without that if I specify a correct connection string ($server . chr(10) . $alias) for Session.Logon

SMTP

this isn't suitable as sending emails isn't what I'm doing. I want to generate a request ID for the email and add it to the subject line and Categories field then ->Move($folder) or ->Save() the item and log some info in a database using Win32::ODBC (which all works fine interactively)...

I knew MAPI was a complete pain but a service account was the sensible option... perhaps I should bite the bullet and install Exchange Administrator to see if that helps (it may be CDO.dll that's missing but the registry tells me that the classes are all defined by OLEMSG32.dll which is there and registered correctly.

Any other suggestions?

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