Firefox 4 shows Unknown Sync Error

I am getting major issues with Firefox Sync to perform its thing and synchronies some data. While syncing I am getting an error message: "Sync meets an error while synchronizing: Unknown error. Sync will automatically redo this action." I could not understand this problem. I don’t think that this error is only for me. Those who have installed the Firefox 4 might be getting same error message. Actually the problem exists among Mac, ubuntu and Windows editions of Firefox 4. I hope that there will be a better way to sync the data manually,

I have done the following thing and it worked for me very well and I think that you should try the same:

• First of all open the Firefox menu and go to the bookmarks > Organize bookmarks. Get there a backup of all bookmarks to continue on the secure side for those bookmarks.
• Now open the sync tab in Firefox preferences (edit -> preferences)

Uncheck the whole thing apart from passwords and close.

• Perform a sync via double clicking the sync inside the status bar (base of Firefox)
• Go backside toward the sync tab and re-enable individually what you require, doing a sync in amid.

I have also got the similar kind of error which doesn’t leads to any solution. If this kind error occurred in a computer then it could be a tragedy for everyone because we can find any specific reason or solution for this issue. So after several tries I didn’t make it work proper and sync correctly. For that reason I have contacted the support team of Firefox. They advised me to delete the account. So I have deleted the account and completed a Re-install. After this everything is working fine so far presently.

In my concern the Firefox 3.6.13 sync correctly however Firefox 4 does not while it used to sync through no trouble. I'm thinking at that moment the update headed for the Firefox Sync servers not at all supports Firefox beta 9 seeing as, via what I've examine, the update altered effects around a bit radically (APIs plus such) therefore I've shut off Sync in favor of beta 9. I thought that the full release of Firefox 4 will be completely without the bugs. But here I think that I am wrong now.

I have seen that there is a new add-on for Firefox add-on is available on the internet or the Firefox official site. This add-on is not necessary for the Firefox 4 because it is already included in that. But still you are saying that you are getting some unknown error while syncing the data. For that I urge you to try that add-on and see what you can get from that. This add-on will offer the access to your history, passwords and bookmarks. If you are using the beta then this add-on is not suitable.

I think that you have downloaded the Beta version of Firefox 4. As far as I know that there are different versions of Beta available on the internet normally from 1 to 9. In order to get the trouble free version of Firefox you will need to download the latest version which just released now. It is actually a full version and normally we called as bug free version. At present there might be some limitations with the sync process but after recent update it may gonna solve.

I got this same error. Sync worked but the error was still annoying. I fixed it by going to manage account Sync and unchecking bookmarks, passwords, preferences, history, and tabs. I closed sync manager and then reopened it and put the check marks back in. It has worked ever since.

As bizarre as it might seem, that did the trick for me as well...