Komunitné fórum Firefox

This is the message I get when I try to access my Bookmarks: "The bookmarks and history system will not be functional because one of Firefox's files is in use by another application. Some security software can cause this problem." I have already tried to find out from Microsoft if their latest reinstallation of Office Professional could have caused the problem. They say they have nothing to do with Firefox. How can I get my Bookmarks and History back?

This morning all my bookmarks have vanished, and I can't recover them using the instructions in the help articles. ALL WERE AVAILABLE LAST NIGHT. My home page is the only thing still there

Several times now I've closed firefox while having the open previous windows and tabs on startup on only for all my tabs to have been closed (with this time in particular being annoying due to losing tabs that I needed to have the specific link for). Is there any way to restore tabs lost in this way?

I think that this recent update removed all of my tabs and tab windows, it has done this before and I don't understand why, I have the old update session file still (The 11/11/2025 One) and I tried to use that one to bring the tabs back by putting the file in the sessionstore-backup folder with no other file in it, but they didn't come back. I am genuinely confused as to why it doesn't work, I have renamed and deleted sessionstore.jsonzl4 files but it still comes up as a new session.

I opened a profile that I had just used recently to a blank tab bar. I closed it and the sessionstore-backup folder did not have a recent backup, The most recent about a week old.

Just for testing, I tried to restore with one of the upgrade.jsonlz4 file, about 2 weeks old, but it also had no session. I then restored one that was 2 months old. That one had a session

Now, Firefox no longer generates the upgrade.jsonlz4 files

Hi, there.

After performing the most recent Firefox update, I was greeted with the "create a new profile prompt", rather than having it open my old one. When going to "about:profiles", ALL FILES in the Root Directory of my old, default profile have the same date as the update, or after. Not a single file is older than that and all my history and bookmarks are gone. The option "Restore Previous Session" was not shown after the update.

PLEASE HELP!!

Thank you.

PS: This happened on a Macbook Pro. All other profiles are the same as they were before the update, having kept all history and bookmarks.

Hi All,

My laptop got damaged this morning and now that I am logging into Firefox with my new laptop its not syncing anything. Many years of bookmarks and stuff is just gone. Is there any way to get it back?

Kind Regards

it's my fault and i don't know what i did: set FF to always restore previous session but closed several multi-tab windows when tabs were restoring, including - i think - truth.social.com, which was carrying one of those windows, possibly misusing the restore all tabs selection.

the best way to help is for you to draw a picture of me, deleting by mistake, and then reporting to you.

i will continue on my own, reviewing the "help" focusing on "restore", and will put as many tabs (ugh) back in windows they belong in. don't worry. it was me, and the effort will be worth it.

thanks for everything moz and FF.

My Bookmarks are missing. I see backups under the profile/bookmarkbackups folder but when I manage bookmarks, they are not in the restore dropdown. I have followed the steps to delete the places.sqlite but when I reopen firefox, I do not see the bookmarks have been restored. I thought it might have been related to Norton Utilities so I renewed a subscription but no luck. I also have a json file with my bookmarks but I cannot choose it from Manage Bookmarks, either

3 times now, my account has completely reset, forcing me to log into everything again and not working with the key that I copy and pasted and downloaded. I would like my old data back. Why does this keep happening?

I updated Firefox to 145.0 this morning, and after Firefox had restarted, it had lost all bookmarks and the bookmarks toolbar. I have spent all day following links to correct the problem and got nowhere. I have restarted Windows and Firefox countless times - no change. I've even tried reinstalling Firefox over the existing version. If I go to bookmarks > manage bookmarks > restore and backup, sometimes that will load, others not. When it does load, it fails to find a file to restore from. 10 years of bookmarks, links & research vanished.

Can someone please provide a solution (preferably in Layman's terms) to this??

To make a long story short, since this morning, Firefox had no more profiles after an update. The one I am currently using, which came to exist this morning and only contains information from this morning, is the only one that shows up when I try to follow the recovery instructions. My internet history beyond today seems to no longer exist. How do I recover my bookmarks and passwords? Or are they gone forever?

After the latest auto update all of my history, tabs/windows, and bookmarks were deleted and I can't recover them. I have tried importing bookmarks and it does not allow me to upload an old data file and I can't restore my previous session. I tried checking both profiles but neither had my information saved and now when I open the about:profiles says "Another copy of Firefox has made changes to profiles. You must restart Firefox before making more changes."

I'm scared to try anything else because I don't want to mess anything up further but I really need my tabs and history back.

I restarted my computer and then reopened firefox and it had updated and I noticed my bookmarks were gone but my windows/tabs were open, so I tried to choose a file on the bookmark backup and nothing was happening so I restarted and after that all my history and tabs were gone and I couldn't restore them.

You forced a download of of the new FireFox and it wiped out everything - favorite, history, etc.. even though I have signed into my profile. I don't even have the option to import from my previous version. WTH?!

Firefox updated automatically. No bookmarks or history??? I cannot find anything. This is my old Windows 10 computer. Have bookmarks on Windows 11 computer. Afraid of updates. any help?

Hi customer service, please help me to restore firefox data & tabs before today. my firefox update this evening crashed & unable to restore. Million thanks

Dear Community,

Since more than a month, when firefox was updated, all my bookmarks seem to be gone,which includes a lot of valuable research made over the past few years.

I have tried all suggestions that google give me to restore my bookmarks, but as far as I understand, there are no newer ones since 2019 (nor older ones than 2018) on my computer? That's what I find in a folder called 'bookmarkbackups' with json-files. Separately I also searched for 'json' and '.jsonlz4' and found nothing after 2019. Also I searched for .html, but nothing seemed to contain bookmark directly.

When I go to manage bookmarks > 'import/export' icon in the upper bar, it suggests two options, for 'nov 13 2025', or today's date), of which none provide me with any bookmarks.

Can I somehow still recover my research?

Do I really need to backup manually?

Or need I start saving all URLs in a word-document for my new research project?...

Firefox seems to update regularly, I currently have version 145.01. (I work on a Mac 2021, with Ventura 13.7.8)

I highly appreciate any advice on this matter.

Kind regards, Maria

Just updated my Firefox. I had a huge tab group saved, and tons of bookmarks. I've been using firefox for months, I didn't have an account signed in on the browser though. I updated it and it had to restart, and everything was gone when it reopened. I even clicked that it should reopen tabs after restarting, but it just opened to tell me to make a profile. It told me that they just introduced profiles, and it put me on profile 1, which looked brand new. No browsing history whatsoever, no bookmarks, my background that I set is gone, and I cannot find anythign at all. I had over 50 bookmarks, inclyding very imprtant links for a final paper, and I'm genuinely so upset. Multiple of those bookmarks were things for me to go back to read/watch later and I will literally not be able to find them. If anyone has any tips at all, I'd love them. I am so seriously upset right now and I'm just hoping its possible for that to come back.