I recently upgraded to firefox 12 which appeared to break my firefox sync and would not allow me to re-pair my PC or any other devices to my account. In order to try fix the problem, I decided to delete my account. Having done this, I created a new sync account from firefox on my PC using the same email address as I had used in my previously deleted sync account. This appeared to work alright and so I tried to pair my iPhone (using firefox home) to this new sync account. I used the passcode firefox home gave me and according to firefox on my PC, the sync was successful. However, a minute late, my iPhone came up with the error message "Login Failure: Unable to communicate with server (503)". I then tried to log in to the firefox sync website with my email address, (https://account.services.mozilla.com/), and got the message "We were unable to log you in". I then clicked on the Forget your password link and entered my email address and got another error message "Unable to locate account. Please check username"! It would appear that deleting my account and creating a new one with the same email address has stuff everything up? I don't want to have to use a different email address.