hi, before you start the password reset procedure at https://accounts.firefox.com/reset_password you get warned that this will wipe all sync data on the servers! this is inevitable because the sync system is implemented with data security as primary focus: your password is the only way to decrypt the data once it leaves your device - if it's gone then the data is useless as well! (also sync is not intended as a backup system but to keep multiple connected devices on a same level)

how exactly did you create the backup of your old windows disk?

Hi philipp Thanks for your help. I've used Windows backup tool for that and the resulting file is encrypted so only a Windows restoring tool would be able to decrypt. Are you saying that there might be a way to retrieve application data files from a Windows backup? Cheers!

i don't think that those backup containers have any particular encryption. there are tutorials on the internet how to extract particular data out of them: http://www.howtogeek.com/125704/how-to-extract-individual-files-from-a-windows-7-system-image-backup/

if you manage to do so, you'll want to create a copy of your old profile folder - this should usually be located on the drive under \Users\<your username>\AppData\Roaming\Mozilla\Firefox\Profiles: Profiles - Where Firefox stores your bookmarks, passwords and other user data

Thanks for your help! That did it!!!! I should stop assuming and start googling! :-)

Thanks again!