Hi 5L5L, Sync can be slow. Are you getting any data back at all (saved logins, bookmarks, history, etc.)? If you want to see what is stored on the Sync server, you can install the following add-on: https://addons.mozilla.org/firefox/addon/about-sync/ After installing that add-on, type or paste '''about:sync''' in the address bar and press Enter to load that internal listing page. It's a little hard to read, but for each type of data, you can see what is on the server. ---- '''''Separate thought:''''' During your Windows 10 Reset, did Windows create a new folder named: '''C:\Windows.old''' ''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.