Firefox Community Forum

CCleaner wiped out my bookmarks and their functionality. I have repaired, then uninstalled CCleaner. I have refreshed, uninstalled then reinstalled Firefox. I have logged in and out of Firefox. I have made an HTML file of bookmarks from another device in order to try to import them. Firefox bookmarks will not proceed to an upload stage. I went into setting to add the HTML of bookmarks and it said "this is not a bookmarks file." Well, Firefox made that HTML bookmarks file so I have no idea how that could be. Nothing I have tried has worked.

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?

Since Firefox automatically updated (14.0.1) on my MacBook Air (2025 model) several weeks ago, the Bookmarks and History functions haven't worked. Can anyone suggest how I can fix this?

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?

Mozillers,

I depend heavily in my environmental and other work on Firefox and am grateful for its ability to restore previous tabs when my laptop, not infrequently, stops working abruptly.

Now the much-used bookmarks have disappeared. A search site states promisingly:

"To restore Firefox bookmarks, use the built-in backup feature by going to Menu > Bookmarks > Manage Bookmarks > Import & Backup > Restore, then select a dated backup or a manual file (like a JSON backup) to bring back lost bookmarks..."

But my Firefox's Bookmarks drop-down menu has no Manage Bookmarks option. PLEASE, what must I do?

Elsewhere I managed to find this file which apparently contains recent bookmarks:

"C:\Users\User\AppData\Roaming\Mozilla\Firefox\Profiles\unk14jlv.default-release-1647366062305\bookmarkbackups\bookmarks-2025-12-26_95_4IdGtYxezJpwuH1UIiT1bRwe1K6bcGO8rv0mqa9rUWU=.jsonlz4"

But attempting to open it with Applications\firefox.exe (default) accomplishes nothing.

FOOL-proof instructions would be wonderful. Thank you.

There was a issue with my computer due to which I had to reset the unit and once the reset was completed I'm unable to recover my data as its asking for 32 account recovery key, I'm unable to find that key anywhere and need help where can i find the key as there are important bookmarks which I need back.

I still have not made any progress recovering my lost Firefox bookmarks. I have tried several methods with no success. The bookmark toolbar doesn't work, so I can't bookmark any more pages. I tried restarting the computer and Firefox to no avail. I am considering switching to another browser. I am using Duck Duck Go which is not as good as Firefox that I have been using for about the last 10 years. I might try Microsoft Edge or Bing or some other browser.

Sincerely

Jeff [email address]

My previous post seems to have disappeared, so will try again. I am 85 years old and have been using Thunderbird fo over 15 years with out any problems. Afew days ago I tried to send an e-mail and didn't have any "Send" button. In trying fix, I some how deleted my contacts sidebar. I sill have my addresses book. I have tried everything to retrieve them but no luck. I tried removing Thunderbird and reinstall, but it comes back the same. I would appreciate an guidance in trying to resolve my problem. Thank You

Hi. I accidentally deleted the "Today" subfolder that exists under the "History" section in Mozilla. How can I get it back? I'm not interested in getting the internet history from today back, just the folder. Thank you for your help.

Siguiendo sus instrucciones facilitadas, he conseguido recuperar la carpeta de mi perfil anterior pero no se qué hacer con ella para que aparezcan los marcadores de siempre en la aplicación, cómo lograrlo Gracias

Bookmarks in Firefox disappeared and cannot import my Bookmarks backup. I have tried to restore an older Bookmark file through /manage bookmarks/ import and backup/restore to no avail. thank you

More of a comment. Firefox is the only browser I have used. Love it! Many important bookmarks to easily navigate. Broser update messed up bookmarks and took me hours to get back! Found. Save key and/or password! Learned a lot about profiles and Firefox along the way. Ugh!

I am incredibly frustrated by the continuing problem of all my Bookmarks disappearing with the usual "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." This issue has been going on since NOVEMBER!!! I usually manage to get my Bookmarks back by closing all txt files that I need to keep open, store them in a new folder on my laptop, and then restart my laptop. This time, it didn't work.

Can anyone steer me to a permanent solution to this problem?

Thanks, in advance, for any help offered.

My laptop crashed and I had to format my hard and install new windows.

I have kept my passwords database files, which uses to be key3.db and key4.db along with logins.json and logins-backup.json files from my old use with me separately...

But the new Firefox folder didn't create these files anywhere where I could replace them with my files to get my stored passwords back.

Please help me restore my data from these files onto my new Firefox so I can get my stored passwords back.

Dear Mozilla Geeks—

As practically every other Firefox user, my bookmarks evolved into a lengthy file system that uses folders to segregate categories of bookmarks.

That is, it used to have this feature.

After the last update all or most of the bookmarks (I can't tell by scrolling down the long list) are devoid of their organizing folders. This puts a great deal of information beyond easy reach. In Mozilla Help topics one is advised to click on the library icon in the toolbar ... only there is no such icon on my copy of Developer's Edition.

Can someone suggest a method or methods to recover the folders?

Some passwords have been lost as well.

Yours Sincerely,

Glen