I use a Microsoft Exchange 2010 email server and a Mozilla Thunderbird client. One day I selected a large part of my inbox and mistakenly pressed a keyboard shortcut which (I presume) marked the messages for deletion. The messages, of course, gets deleted. Now, the funny part begins: if I restore the deleted messages using "Recover deleted messages" feature in Outlook, the messages get back to the inbox BUT, as soon as I start my Thunderbird client, it deletes the messages again.
Now, as stated by this kb (http://kb.mozillazine.org/Deleting_messages_in_IMAP_accounts) the messages should have a "deleted" flag, so: How can I clear that flag?