trouble starting outlook with virus software running

[Guest]

When i open Microsoft Outlook with a limited user account
and with McAfee antivirus running i get the following
error message.

Unable to open the activity log file C:\Program
Files\McAfee\McAfee VirusScan\WebEmail.txt. This file is
either write protected or locked by another application.

I also get it on shutting down Outlook, but end up having
to shut Outlook down via the end task in task manager.

However i get no problems if i shut down antivirus.

Can you help please?

Thanks Patrick