Firefox Community Forum

Recovered files and data from a failed M.2 SSD onto a USB. Did a clean install including reinstallation of Firefox on the failed machine. How do I recover the Firefox profile from the recovery USB so it can be transferred onto the restored machine?

Every other day, I open FireFox and may get the following error: XULRunner - This profile was last used with a newer version of this application. Please create a new profile. Also, this error may come up while I already have had FireFox open for a while. Once this error comes up, I check the version, and sometimes the version is older than what it was, meaning, FireFox reverted back to an older version on it's own. I created a new profile, but the error comes back. I removed FireFox and all folders, and the error still comes back. There is nothing I can do to stop the error from showing up again. See attached images. I am on Windows 11 23H2, all windows updates caught up, and the current FireFox browser version is 138.03.

hej, you write oh dear, no print is possible :-((( but you write to me, that I have win10... but it is a new machine with win 11...and firefox does not work, i cant se my mails?!?!!?

When i upgraded Firefox my old profile doesn't show up now. I found my old profile under about:profiles but when i click on the Launch profile in new browser i get this message, "You've launched an older version of Firefox. Using an older version of Firefox can corrupt bookmarks and browsing history already saved to an existing Firefox profile. To protect your information, create a new profile for this installation of Firefox" I did create a new profile but how do i get my old saved data, add ons etc to the new profile?

I have a bunch of profiles set up via "about:profiles". Some of these are associated with different Mozilla accounts, some are not. Today, I wanted to rearrange those profiles to put some older profiles that I do not use as often lower on the page than more recent profiles. I thought I remembered there being an overview text file that included a number for each profile, the folder that profile's information was stored in, etc. When I went looking for that file, I could not find it, so I went looking for help articles and discovered that there is a new profile management tool.

When I tried using the new profile manager via "about:profilemanager", none of my current profiles are visible, so I cannot use that tool to reorder my profiles.

I would be grateful if you could point me to an article explaining how to reorder the profiles in "about:profiles". If that is not possible, I would appreciate a help article explaining the rationale for making these two uses of the word "profile" distinct, the ways in which these profiles are different from each other, and how to transfer settings from the older version to the newer version. I have everything set up just the way I like it within my current profiles and really do not want to have to recreate them from scratch...

I did not ask for and do not want profiles at all. It seems this was added when firefox updated? How do I get back to the old version with no profiles. It also lost all my bookmarks etc. Help would be appreciated.

Hi - Firefox placed an 'Old Firefox data' folder on my desktop and I am unable to delete it. I'ver tried third party apps, logging in as administrator, command line delete, uninstalling FF but am still stuck with it and my network settings are wrecked so I can't re-establish connection to the internet on that machine. Anyone with any suggestions as to how I get rid of the 'Old Firtefox data' folder ? Many thanks...