Komunitné fórum Firefox

Near the top of the Firefox page is displayed:

"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 caused this problem".

How do I resolve this problem?

Hello

When trying to visit some websites the connected server returns timeout in Firefox. Attempting exactly the same site from out Edge it answers at once.

The machine is a up to date Windows11 pc with an active Mozilla VPN.

Should I change some settings? How can I find out the reason?

I have over 100 open tabs spread over 4 Mac desktops. I can no longer access ANY of them after upgrading to macOS Tahoe 26 and installing ESET Cyber Security Pro. I've used ESET with Firefox for many years without ANY problems. But now I have to choose between uninstalling ESET and being unprotected in order to use Firefox AT ALL. Every single webpage is blacked out with the message below. ESET support says that Firefox needs to issue an update to fix this problem.

I am using AdGuard Windows App but the app does not work well with Firefox. There are long page loading delays on many sites (TLS handshakes, etc.) while I do not have this issue with other browsers. I have installed the AdGuard certificate, have disabled DOH in Firefox, but still the problem. The only solution is to turn off HTTPS filtering in the AdGuard Windows app which then defeats many of the protections normally afforded by the AdGuard Windows app. I understand that there is a long history of Firefox not playing well with AdGuard Windows app so I am hoping/wondering if there is some solution on the horizon?

After instalation Eset Smart Security 18.2.18.0 with full security browsers my Firefox is run only in read-only mode. If I will be disable option Security browser and run Firefox that's working. Next I will be enable option Security browser then Firefox starts with green frame. After close Firefox and next run then starts read-only mode. Eset Team is not fair play becouse resolving problem only disable option Security browser. So why is there an option that prevents Firefox from launching? All my portable browsers without Eset Security working without any kind of problems, for example Tor, Opera.

My bookmarks, history and passwords have disappeared. I looked at the articles, refreshed firefox, have restarted firefox and my computer multiple times but cannot retrieve them.

This is the message when I start firefox

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.

Hi, I have been trying all day to get my Trend Micro program working on my Firefox browser, including Password manager. These programs work ok on MS Edge browser, but I can't get it to work on my Firefox browser

For the past few days hot links in Thunderbird do not open in Firefox. Selecting a link in an email opens or brings to the fore a copy of Firefox with the link address and the wait icon but nothing else happens. I have to close Firefox, copy the link location, Past and Go in Firefox, and then the linked page appears. This behavior happens even in Troubleshoot Mode, so it is not any plugin or customization. I am also running Mozilla VPN. With VPN disabled, hot links in Thunderbird open in Firefox as expected. Now you know where to look.

Also, when I tried to add Troubleshooting Information below, nothing appeared. When I selected to option to be shown what to do, this page was replaced with other which deleted all this text, and now I am entering it all in again, which is severely frustrating. On a page where the user has entered possibly a volume of information, there should not be any sloppy risk of deleting that information due to page mishandling. Open help or assistance information in a separate tab, please. Think ahead about this stuff. You are supposed to be web design experts. Instead your web site spits in my face just when I am asking for help. Think. Plus, I had to get the Troubleshoot information manually so that is not being as automatic as it appears to be , either. Getting help should ideally be a button click, not jumping through hoops.

Like many, I have Windows 10 and cannot upgrade to Windows 11 without purchasing a new computer. I don't want the upgrade as my desktop computing needs are simple -- checking email and occasional online research. I am looking at 0patch as a solution to Microsoft discontinuing support for Windows 10 and want to know if Firefox will operate compatibly with 0patch providing security patches instead of Microsoft.

I'm not a technical person, so please keep replies simple. At 80 it's tough to keep up with all the changes! Thanks.

Bonjour. Depuis longtemps j'utilise Firefox Portable dand un bac à sable(SandBoxie-Plus). Depuis la dernière mise à jour Firefox plante, affiche incomplétement ou pas du tout la page. Je signale que sans le bac à sable Firefox fonctionne normalement. Actuellement je suis sur "WATERFOX" portable (version mai 2025) qui a l'air de fonctionner normalement.

RESTORE A TRUSTED RECIPE SITE banned by Mozilla: recipestonourish.com  !

I have been using this site for years. This morning Mozilla ruined it. Please restore, thank you!!

Carla van Raay [edited email from public]

Perth Western Australia

Hello, I'm an avid user and supporter of Mozilla Firefox. But I installed AVAST as an additional protection tool...and I have just subscribed today to Avast Antitrack to avoid being tracked and hacked. But, to enable AntiTrack, I'm now prompted to add it to Firefox !? Before any action, I'd like to know that this will be efficient and safe : can you confirm that this is compatible with Firefox's proper operation? Thank you, P.Huens.

Hello,

we are observing big issues with mozilla firefox.

Few weeks ago it was impossible to use amazon with it.

Amazon support recommended us to not use the anti virus anymore, which was very strange. but it did not help.

After I add the antivirus addon to firefox it started to work. Unfortunatelly just for few weeks.

Actually we receive the following error and cannot browse or do anything Fehlercode: PR_CONNECT_RESET_ERROR

We have tried follwoing without success: - clearing cache - using problem investigation of firefox below button "help" - deinstalling and installing - installing the beta version

already after installation of firefox where normally terms and conditions to confirms shall appear we get the failure Fehlercode: PR_CONNECT_RESET_ERROR nd the content cannot be downloaded.

Hence Amazon does not work below google neighter and firefox is the only way o use amazon, we will appreciate your help.

Looking forward for your help

ags

Lost all of my bookmarks. Error message reads: "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 been a Firefox user for years and years. I am having to leave because I cannot resolve this new issue. Can you help?