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Sync didn't restore my data after installing new Windows 10 & Firefox

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I assumed sync feature backup my bookmarks and saved passwords and I can readily access them in my new windows! As other browsers does this routinely. So I'd synced in my previous Firefox account just before installing new Windows 10. Now, I cannot access any data of my account.

How can I restore them?

I assumed sync feature backup my bookmarks and saved passwords and I can readily access them in my new windows! As other browsers does this routinely. So I'd synced in my previous Firefox account just before installing new Windows 10. Now, I cannot access any data of my account. How can I restore them?

Réiteach roghnaithe

Unfortunately, if you don't have a copy of the data and the data is not coming back when you sync, you are out of luck.

Firefox Sync IS NOT A DATA BACKUP SERVICE. It was not designed to be one, so it doesn't function as one. It does not necessarily keep a complete or permanent copy of your data on the servers. It's designed to sync your data between multiple devices, not to backup your data.

For the correct backup procedure, see Back up and restore information in Firefox profiles.

When you say you installed Windows 10, does that mean you formatted your drive or did you use the Windows reset feature to revert the OS back to it's factory state? If you used the reset feature, your previous data might be located somewhere within the windows.old folder that Windows 10 will often leave behind when it's reset.

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All Replies (3)

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Réiteach Roghnaithe

Unfortunately, if you don't have a copy of the data and the data is not coming back when you sync, you are out of luck.

Firefox Sync IS NOT A DATA BACKUP SERVICE. It was not designed to be one, so it doesn't function as one. It does not necessarily keep a complete or permanent copy of your data on the servers. It's designed to sync your data between multiple devices, not to backup your data.

For the correct backup procedure, see Back up and restore information in Firefox profiles.

When you say you installed Windows 10, does that mean you formatted your drive or did you use the Windows reset feature to revert the OS back to it's factory state? If you used the reset feature, your previous data might be located somewhere within the windows.old folder that Windows 10 will often leave behind when it's reset.

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Wesley Branton said

Unfortunately, if you don't have a copy of the data and the data is not coming back when you sync, you are out of luck. Firefox Sync IS NOT A DATA BACKUP SERVICE. It was not designed to be one, so it doesn't function as one. It does not necessarily keep a complete or permanent copy of your data on the servers. It's designed to sync your data between multiple devices, not to backup your data. For the correct backup procedure, see Back up and restore information in Firefox profiles. When you say you installed Windows 10, does that mean you formatted your drive or did you use the Windows reset feature to revert the OS back to it's factory state? If you used the reset feature, your previous data might be located somewhere within the windows.old folder that Windows 10 will often leave behind when it's reset.

Unfortunately, I had to do disk partitioning so there is no windows.old folder.

It's a shame that Firefox sync doesn't function as a backup for necessary data like similar ones. So, you mean if somehow suddenly firefox or windows is removed, there will be no backup of our data in Firefox sync? It's really unfortunate and I think it would be a reason for me to migrate to other browsers...

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Unfortunately, that's just not what it was designed for. Some changes have been made to Firefox Sync to bring it closer to that direction, but it's not reliable when used as a backup service.

Alik said

So, you mean if somehow suddenly firefox or windows is removed, there will be no backup of our data in Firefox sync?

If Firefox gets removed accidentally, it doesn't matter because the data saved by Firefox isn't touched during the uninstall process (unless you use one of the few unsupported third-party uninstallers that does take that data away).

If Windows is removed, yes. However, it's important (and is common practice) to backup any data that you want to keep before removing Windows from your computer.