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Bookmarks have disappeared and unable to restore

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While browsing today, and going to a website via my bookmarks, I noticed that suddenly all my bookmarks had disappeared and I had the "Bookmarks and history system will not be functional because one of firefox's files is in use by another application" message.

I followed the instructions (restarted computer, renamed places file and tried to restore old backups but nothing works. When I try any old bookmark backup, I get the error message "Unable to process the backup file."

When I check for integrity, I get the following error message. Please help!

> Task: checkIntegrity - Unable to check database integrity > Task: invalidateCaches - The task queue was cleared by an error in another task. > Task: checkCoherence - The task queue was cleared by an error in another task. > Task: expire - The task queue was cleared by an error in another task. > Task: vacuum - The task queue was cleared by an error in another task. > Task: stats - The task queue was cleared by an error in another task. > Task: _refreshUI - The task queue was cleared by an error in another task.

While browsing today, and going to a website via my bookmarks, I noticed that suddenly all my bookmarks had disappeared and I had the "Bookmarks and history system will not be functional because one of firefox's files is in use by another application" message. I followed the instructions (restarted computer, renamed places file and tried to restore old backups but nothing works. When I try any old bookmark backup, I get the error message "Unable to process the backup file." When I check for integrity, I get the following error message. Please help! > Task: checkIntegrity - Unable to check database integrity > Task: invalidateCaches - The task queue was cleared by an error in another task. > Task: checkCoherence - The task queue was cleared by an error in another task. > Task: expire - The task queue was cleared by an error in another task. > Task: vacuum - The task queue was cleared by an error in another task. > Task: stats - The task queue was cleared by an error in another task. > Task: _refreshUI - The task queue was cleared by an error in another task.

Isisombulu esikhethiweyo

Hi, you maybe out of luck with it. Or maybe able to rescue something from it. If Syncing and the bookmarks are good on the other device (you are using another device as syncing is not for backing up and this can happen or worse.) If another device unhook it from syncing so that you have a good copy left on the other device to rescue from.

Reinstalling will not help as this is in the Profile which is not in the same place as the program.

Do this with Firefox not running please.

Create a new profile :

Your bookmarks are in :

If can not get anything working from the other device or these corrupted ones then try this to get to the data URL's :

  • If a jsonlz4 backup can't be imported restored because it has the same structural problem as the database,

A user can try to fix it using the Check/Repair JSON button on this page:

fyi for the future as sync does not replace backing up :

Please let us know if this solved your issue or if need further assistance.

Funda le mpendulo kwimeko leyo 👍 1

All Replies (6)

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Can anyone help please? This is a problem which is really quite affecting me.

Would a clean uninstall/reinstall with subsequent syncing help? The bookmarks still seem to be there on firefox on an old laptop of mine?

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Isisombululo esiKhethiweyo

Hi, you maybe out of luck with it. Or maybe able to rescue something from it. If Syncing and the bookmarks are good on the other device (you are using another device as syncing is not for backing up and this can happen or worse.) If another device unhook it from syncing so that you have a good copy left on the other device to rescue from.

Reinstalling will not help as this is in the Profile which is not in the same place as the program.

Do this with Firefox not running please.

Create a new profile :

Your bookmarks are in :

If can not get anything working from the other device or these corrupted ones then try this to get to the data URL's :

  • If a jsonlz4 backup can't be imported restored because it has the same structural problem as the database,

A user can try to fix it using the Check/Repair JSON button on this page:

fyi for the future as sync does not replace backing up :

Please let us know if this solved your issue or if need further assistance.

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Thank you, creating a new profile solved it!

Can I now delete the old "default" profile? And rename the new one to "default"? Or does renaming the new one not matter?

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No need to rename the new profile. Firefox already knows exactly how to find it.

Did you already transfer over any data you wanted? In that case, you no longer need the old one. However, you might give it a week in case there's something you don't currently notice missing that you'll want back.

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Thank you! Would syncing (which seems to have worked as it transferred all the bookmarks etc) have transferred all the data (at least in theory) already?

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Mugo said

Thank you! Would syncing (which seems to have worked as it transferred all the bookmarks etc) have transferred all the data (at least in theory) already?

When it's a nice sunny day, Sync handles it completely. If there are storm clouds, things can go missing. It's up to you how long you want to keep the old data for "insurance."