I'm having this problem since few releases ago, whenever I start FF, it always fails to sync, showing this line on the bottom "Sync encountered an error while syncing: Incorrect account name or password. Sync will automatically retry this action". First thought that the prob was incorrect credentials, but I can freely log-in https://account.services.mozilla.com I tried unlinking and linking my device again, it still happens. I waited thinking that they'll fix this, from a release to another, today updated to the last version and it still happened.
Windows 7 Ult SP1
Awaiting reply, Thanks.
Try to clear the mozilla.com cookies.
Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).
You can also try to unlink the current device and try to run the set up again or delete the current Sync account and start anew.
(this reply is only to bookmark this thread)
We believe we fixed this problem in Firefox 17 and newer. You can install Firefox 17 today by downloading Firefox Beta.
Problem still ocurred in 17 on linux, however I found a suggestion in one of the other threads about this issue to unlink, close FF, remove places.sqllite in FF's profile directory, restart and re-setup sync.
This fixed the issue for me (and I got my bookmarks back) :-)
I am having this problem with FF 19.0.2 on Win 7 Pro. The sequence of events is:
1. Start Firefox. Get the error bar about incorrect account name or password EVERY time. I close the bar. If I wait a while and then ask FF to try again the error bar reappears.
2. Click on preferences from the bar, and get a dialog "Your password was rejected by the server, please update your password." I click "update" and then am prompted for the master password for the security device. I enter that and am presented with an "update password" dialog.
3. Enter my old password and click "update password." Receive error message "Password incorrect, please try again." I click update again and get the message "Your password has been changed."
4. However now Sync no longer seems to be set up. I go through the setup ritual again, and find I am back where I started.
I have cleared cookies, tried everything in safe mode, and unlinked and relinked the computer. I have verified I have the right password entered at https://account.services.mozilla.com/ None of this helped. The problem is still there, even in safe mode.