For some ungodly reason Microsoft thought it wise to mess with our minds when using IMAP… I don’t know why they thought this was a good idea, but Outlook places a strike thru line in messages that are pending deletion. This in my opinion is very annoying, there is no reason a person would want to see this by default. When you delete something it should be deleted. If not, please lie to the user and make it at least look like it has been deleted.
Basically, whats happening is Outlook is holding the messages in queue, until they are purged. To purge them:
1. Click Edit
2. Purge Deleted Messages.
To hide the messages until they are purged (remove/hide the strike thru messages):
1. Click View
2. Click Arrange By
3. Click Current View
4. Click Hide Messages Marked for Deletion