I seem to be having problems with Sophos AV marking emails as encrypted. It seems to be mainly emails with .xls attachments but when looking at the email or the attachment cant see why the email is being marked as encrypted. This is not all emails with xls attachments but the odd 1 or 2. We also have Sophos saying some xls files are unscannable.
We also run McAfee on the same boxes and they are marking the emails as clean and having no problems scanning the emails.
We currently set all encrypted based mails to be quanrantined. Would also like peoples views on this should we let them through or block/stop them getting through to the user?