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Sync never completes

  • 6 replies
  • 1 has this problem
  • 3 views
  • Last reply by FredMcD

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Windows 10 (1903). Quite often I find that sync never completes, the spinning wheel, it just keeps spinning. I have to exit Firefox and restart, and upon restart I need to kill the previous Firefox instance. Then, and only then, will sync work. But not for long, usually in a few hours it's hung up again. This only happens on my Windows 10 machine (sync works fine with my FF mobile and Windows 7 devices).

Windows 10 (1903). Quite often I find that sync never completes, the spinning wheel, it just keeps spinning. I have to exit Firefox and restart, and upon restart I need to kill the previous Firefox instance. Then, and only then, will sync work. But not for long, usually in a few hours it's hung up again. This only happens on my Windows 10 machine (sync works fine with my FF mobile and Windows 7 devices).

All Replies (6)

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Hi Drewskers, Check into why Firefox is hanging. See this article for some help with that: Firefox hangs or is not responding - How to fix

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My_Cheese_Is_Slippin' said

Hi Drewskers, Check into why Firefox is hanging. See this article for some help with that: Firefox hangs or is not responding - How to fix

Thanks for the reply but that article doesn't address the problem I am having. Specifically, Firefox is not hanging! I can still browse normally.

The problem is that Firefox SYNC starts but never completes. It is the SYNC icon, visible under my account name in the 3-bar menu in the upper right corner, that spins perpetually. I hope that clarifies the issue!

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We need to look at the sync logs.

Note: Do the following for each problem system/profile. And label each as to what system/profile.

Type about:sync-log<enter> in the address bar.

Open the last file created and Copy its contents Now Paste it into this forum.

If the file is too large;


Open a text/word program and load the file. Left-click once. Now <Control> A to highlight everything, then <Control> C to copy it.

Next, have your web browser go to; https://pastebin.com/

Paste <Control> P the content of the file in the window. Note: On the bottom, fill out the boxes as best you can.

Now press Create A New Paste. The page will reload. Copy the new web address, and post it here.

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Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

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FredMcD said

We need to look at the sync logs.

Thanks FredMcD. I have just one profile. Here is the latest sync log that captures a failure. (There's been a couple of successful syncs since then, that I initiated manually).

https://pastebin.com/51neReX8

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cor-el I see errors after line 40