If you used the built-in Windows 10 "refresh" feature, Windows usually preserves your data. If you formatted the disk or used a recovery partition, your disk may have been completely erased.

In the first case, check Windows' File Explorer to see whether you have this new directory:

C:\Windows.old

That is temporary folder that Windows retains for 28 days and it would have your old Firefox data.

If you find that folder:

Set Windows to show hidden files and folders -- this Microsoft article has the steps:

https://support.microsoft.com/en-us/windows/view-hidden-files-and-folders-in-windows-97fbc472-c603-9d90-91d0-1166d1d9f4b5

Then explore that folder up to this point (if it exists):

C:\Windows.old\Users\<username>\AppData\Roaming\Mozilla\Firefox\Profiles\

If you find recent data there, please pause and we can suggest how to resurrect your saved files.

Hi, these are the files I found where you suggested I search. What's next? THANK YOU! 23p2fto4.default and 309gz60n.default-release Paul

Hi Paul, one of those will have the latest bookmark backups. If you double-click into one of those folders, you should find a folder named bookmarkbackups. Double-click into that folder and check the file names, the file creation date is coded into the file name, along with a number indicating the total number of items. You can right-click > Copy the latest backup, go back to your desktop, then right-click > Paste the file.

Back in Firefox, you can use the Restore feature to replace your current starter set of bookmarks with the ones from that backup. When you get to the Restore menu, you'll need to select "Choose File" and point Firefox out to your desktop where you pasted it. (Or you can drill down through the various folders if you prefer). See: Restore bookmarks from backup or move them to another computer.

Any luck?

You can check the file date to see which profile is most recent. The compatibility.ini file in a profile contains what Firefox version last used this profile.

The name of an automatically created JSON bookmarks backup in the bookmarkbackups folder includes a total item count (folders and separators included) and an hash value to prevent saving the same backup more than once. You also see this count in the Restore menu drop-down list.

• bookmarks-YYYY-MM-DD_<item count>_<hash>.jsonlz4.

I went to the same location that I found the files in and they are gone. I don't know how to access them again. Any suggestions??? Thanks, Paul

Firefox uses two locations for the Firefox profile folder. One location for your personal data (e.g. bookmarks) and another location for temporary files like the disk cache, so make sure to look in the correct location.

Location used for the main profile that keeps your personal data (Root Directory on about:profiles).

• C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>