At work we unfortunately switched to Google Apps for email, calendar and document storage - giving an us-american company access to our sensitive mails and contact data. Maybe one day they decide to disable our accounts and all data are lost, but our admins probably do backups and replacement servers will be setup instantly.</sigh>
When switching my email client - Claws Mail - to the new IMAP server (just changing the account settings), I got many errors in the network log, and moving mails did not work anymore:
WARNING: IMAP error on imap.googlemail.com: STATUS error
WARNING: IMAP error on imap.googlemail.com: UID COPY error
It turned out that I had to re-sync my folder tree - the errors vanished after that was done. Do that by right-clicking the account in the folder tree and select "rebuild folder tree".