Diễn đàn hỗ trợ Firefox

When I try loading certain sites while using Proton VPN i get the following error message: Server Not Found. If I disable Proton VPN and enable the VPN on Firefox the site come right up. Can someone please tell me why this happens and how I can make these load using Proton VPN?

WHY DO I KEEP GETTING THIS ERROR???

"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 never got this before but now i get this every week. restarting my computer does not fix the problem. this sucks! the article to fix this are way too complicated. how do I fix this? I use Ccleaner and reboot, but that does nit fix the issue either. HELP!

Every new version of firefox just gets slower and slower. Now with version 152.4, I try to load a website, it just continuously tries to load, doesn't even if load the page just has those 3 dots to indicate it is loading. Nothing ever loads

I am starting to think switching from firefox is necessary at this point because no other browser has this issue like firefox. No other browser consumes a ridiculous amount of memory like firefox does.

I did adjustments to my anti-virus as recommended, did the settings changes on firefox to speed it up as recommended, still same issue.

When you guys create a new update, please focus on speed over security and ensure it loads faster. I am likely going to revert back to an older update or switch browsers, because I don't care about security so much as actually loading a website.

Certain websites can be reached and displayed, however when using their page search, it says access denied on this server. I've tried using another browser but the same message comes up. However, on my phone, and tablets, I have no problem.

hello team, I currently locate in China. days ago i have tried a vpn called "Veee". since then i could not log in many websites. i have asked Veee team but they say they dont know. it really sucks. i also asked AI tool but none of the method works. i think the vpn has changed some settings of my Firfox. because i can actually log in those websites with Edge. but i only want to use firefox. the errors either "cant connect" or something like refusing my access. please help. i love you guys.

I have been unable to access any secure sites since I installed Norton 360 Antivirus. Whenever I try to access a secure site I receive the reply: Secure Connection Failed Error: PR_END_OF_FILE_ERROR I have tried all of the repairs listed on the internet but none have corrected the fault. I have also tried disabling Norton but also without success I have also tried uninstalling and re-installing Firefox but without success Can you suggest any other methods to correct this fault

I continually get error messages for webpages. I turn off my VPN, clear my history. Not sure what else I need to do. Last one was the webpage for Lindt Chocolate. Come on. Why am I getting error messages for this? I have been on this page before. There are other places also, like Macys. Getting fed up with Firefox.

Firefox only works properly if my VPN location is in Canada, but I'm in the US. If I switch my VPN to a US location (where I live), Firefox often does not work properly. I get news, ads, etc., that assume I'm Canadian. And often a website will not open. I need my VPN location in the US to access any site I normally do.

Ich habe die Firefox-Einstellungen von einem alten Windows10 Rechner auf den neuen Windows11 PC mit den Profildateien übertragen, hat gut geklappt.. Jetzt hatte ich die Meldung erhalten " der Treiber cpuz419_x64.sys konnte nicht installiert werden wegen möglicher Virus-Gefährdung", als Abhilfe wurde angeboten die Ker-Sicherung auszuschlaten. Das habe ich mir nicht getraut. Als weitere Info erschien eine Seite, auf der "Windows10" unterstrichen war. Könnte das alte Profil dem Rechner vorgaukeln, dass ich Windows 10 nutze?bold text

I installed update 149 and since then, the VPN (NORDVPN) often will not start up and I have to restart the computer. If this cannot be fixed, I would like to go back to the previous version which gave me no trouble. thanks Brian

why am i being asked to sign in to age verification sites when i have mozilla paid VPN installed and have enabled japan as the start point rather than UK  ? - Thanks

April 21, 2026 Tuesday

Thank you for your being here as a volunteer to answer this type of question:

IS eset.com security software compatible with Firefox Mozilla ?

Thank you,

Oliver Jeffrey

east@west.net 24/7 LA California

I was in contact with Bitdefender Support and they suggested the following:

If Facebook still won't open, open Bitdefender and:
  - Go to Protection > Online Threat Prevention > Settings.
  - Turn OFF "Encrypted Web Scan" temporarily.
  - Now reload Facebook in Firefox.

Afterwards, I also had to click on "Messenger" to get all my contacts.

This is temporary since before FF 150, Bitdefender ran with "Encrypted Web Scan", and I had no problem in loading Facebook. So something that changed in FF 150 conflicts with Bitdefender's "Encrypted Web Scan".