Q: I see "Not authorized to sign in at this time" when I try to login to QQ or Tencent Messenger.

A:  Before Tencent releases a new version of QQ/TM to the general public, first some testers can test the new version and give their feedback. Users that are not specifically invited for this private test, will get the above mentioned error. It probably means you downloaded a new version of QQ from a non-Tencent site. Solution: download the most recent publicly available version from QQ or TM (at the moment QQ2007 and TM2008). See my QQ signup page for more information.