"Sync is currently experiencing problems. It will be back shortly."

When I woke up this morning, my Droid told me that it could no longer log into one of my Google Apps accounts. I ensured the password was correct and tried to log in again, but it still failed. Just to be sure nothing was amiss with my account, I logged into the Google Apps account from my desktop.  There were no issues.

After digging in a little, I found that the error was caused by Google Sync failing to sync this Google Apps account's email. I found this by going to:

• Menu -> Settings
• Accounts & sync

Near the bottom of the screen, I saw the error message, "Sync is currently experiencing problems. It will be back shortly."  Googling for this didn't bring any solutions.

After a little head scratching, I decided to log into my Google Apps account from the standard Gmail page (gmail.com), not from the Google Apps mail login page. When I did so, it told me that my Google Apps account was already associated with a Google Account, and that I'd need to take steps to "upgrade" my Google Apps account. Once I finished those steps, my Droid magically starting syncing email for my Google Apps account again.

Hope this can save you some headaches.