If you previously patched your game client to Update 18 Patch 1 prior to today's (5/30/13) fix at 3:00 PM Eastern, then you will need to take an additional step in order to be able to log into the game. The following workaround should also fix any players stuck in a "running loop" scenario with their game log in. Players currently experiencing a "running loop" issue with their game launcher will also need to reboot their computer, and perhaps manually shut down their game launcher, before taking the following steps:

  1. Click on the Windows "Start" button and choose Computer/My Computer from the list.
    (Windows 8 users: swipe in from the right and click into "Search" then type "C:\" (no quotes) and hit enter, then skip to step 3 below.)
  2. In there double-click on your C: drive (may display as "Local Disk C")
  3. Double-click on Program Files (note: if you see "Program Files (x86)" double-click on that one instead)
  4. In that folder double-click on the Turbine folder and then the Dungeons & Dragons Online folder
    (Steam users: double-click on "Steam" > "Steamapps" > "Common" then the Dungeons and Dragons Online folder in there)
  5. Open the Backup folder
  6. Copy the entire contents of your backup folder (Ctrl + A to highlight all, Ctrl + C to copy)
  7. Go back to the Dungeons & Dragons Online program folder (Click the Back button in the upper left corner of the folder window) and press Ctrl + V to paste, choosing Yes to All when prompted to overwrite files.
  8. Upon relaunching the game (once the patch servers are back online) it should proceed to redownload the most recent patches.

Alternatively, a full re-installation of your game client would also solve this issue, although this workaround should get your client patched up without the need for a re-installation.