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Firefox Sync: "Sync encountered an error while syncing: Unknown error. Sync will retry this action."

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  • Last reply by guigs

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So whenever I log into sync I get the error "Sync encountered an error while syncing: Unknown error. Sync will retry this action." It used to work perfectly, but suddenly it stopped. I have tried refreshing Firefox, but that didn't help. I use Firefox on multiple computers, and it's only this one computer that fails. But it is my main computer, so it's pretty annoying. Any help would be appreciated, and I have a Sync log here: "http://pastebin.com/LJnYgUNj".

So whenever I log into sync I get the error "Sync encountered an error while syncing: Unknown error. Sync will retry this action." It used to work perfectly, but suddenly it stopped. I have tried refreshing Firefox, but that didn't help. I use Firefox on multiple computers, and it's only this one computer that fails. But it is my main computer, so it's pretty annoying. Any help would be appreciated, and I have a Sync log here: "http://pastebin.com/LJnYgUNj".

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Try this, there is an error in the debug line about passwords. First disconnect the account, and make a backup of the profile: Back up and restore information in Firefox profiles

Second connect the account by signing in and uncheck passwords. Go into your password manager and see if there are any corrupt entries. Is this file locked in your profile folder? I do not know why it says its locked or undefined, but we can eliminate the local file being locked by checking this file in your profile: key3.db and logins.json