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Firefox Portable

Firefox 52-x error "Access Denied You don't have permission to access...this site...on this server. Reference#...

Submitted by hmp on February 13, 2022 - 10:04am

This error shows only on Firefox 52 to the newest version, and happens whenever I click to check out on some shopping websites, like and
For troubleshooting purposes, I copied my portable Firefox setup and added a gift card and filled in my email address on Costa website:
I checked to check out, but the error page shows instead of allowing me to proceed to payment.

[Fixed] Firefox, Thunderbird, SeaMonkey don't portablize prefs.js paths other than drive letter

John T. Haller's picture
Submitted by John T. Haller on February 6, 2022 - 8:33pm

I realized that the Firefox, Thunderbird, and SeaMonkey Portable launchers aren't fully portablizing paths within prefs.js. They portablize the drive letter, so you're good if you use it on an external drive or locally. But they were never updated to portablize partial paths so they'll work properly from a synced cloud folder between PCs or if you move the PortableApps directory.

I just got robbered on exchange

Submitted by pau_vr on January 24, 2022 - 8:45am

I logged into Kucoin (Crypto exchange) through firefox portable.

In 3 minutes all my funds were transformed into BTC and transferred to another account.

I lost all my funds.
Afterwards I saw that when I logged-in, in parallel another instance logged in in China (time UTC+8).

Pay attention. The software is not safe to be used.
I will ask "" to respond about this unacceptable issue.

My ff 57 ESR crashes even in safe mode

Submitted by mozfan on January 21, 2022 - 3:53pm

Almost every time it starts it's asking to restore previous session even though my option is set on starting with new tab. Changed 1 to 0 in about:config as someone suggested - same thing...Aside from general slow start-up, works fine otherwise and closes without warnings or errors. I shut off power to the PC daily. Any ideas?

Is FirefoxPortable really Portable?

Submitted by atztek on January 9, 2022 - 3:59am

Nearly a year ago I installed FirefoxPortable on PC1 in some directory on disk E:. Now I copied it to PC2 to some directory on the C drive. Firefox on PC2 didn't recognize existing profile folder, let's call it 'ProfileNew', instead it automatically created new folder 'profile' in 'Data' directory. I ran 'about:support' and saw that in 'profile folder'.

Bookmark Bar gone / Firefox warning.

Submitted by IEBAcom on January 6, 2022 - 3:28pm

Been using Firefox portable just fine for months, but now my Bookmarks bar is gone and I see this:

"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."

Which links to this:

Não foi possível baixar o arquivo

Submitted by Alex Oliveira on January 4, 2022 - 10:28am

--------------------------- Platform
Não foi possível baixar o arquivo. Isso pode ter ocorrido devido à um problema com o proxy ou a rede ou ao servidor do arquivo não permitir downloads a partir da sua localização atual. Arquivo:

Can't Pin to Taskbar from USB Drive

Submitted by gaveitatry on December 27, 2021 - 8:20pm

A long time ago, I moved and FirefoxPortable to my D drive. I did this because I also had OBSPortable installed and I could not get OBSPortable pinned to the taskbar from the USB Drive. Once I moved FirefoxPortable and OBSPortable to the D Drive, both would pin no problem. But this week, I uninstalled OBSPortable. I'm just using FIrefoxPortable now. And I want to install OpenOfficePortable too. I'd like to move both of these to my USB Drive, but I'm running into a problem where FirefoxPortable won't pin to the Taskbar from the USB Drive. Any idea why?

Firefox creates local profile adding to portable

Submitted by SomebodyToLove on December 8, 2021 - 8:15am

Windows x64, Firefox 78.15, copied on local system disk
I have quite strange situation: when I run Firefox from shortcut, it uses profile from ...\FirefoxPortableESR\Data\profile as expected, but when I press a link from email, it switches to %APPDATA%\Roaming\Mozilla\Firefox\profile which is definitely not what I want. Moreover, I see all that bunch of mozilla folders in %PROGRAMDATA%, %APPDATA%\Local, %APPDATA%\LocalLow and %APPDATA%\Roaming. So what's wrong with me/Mozilla/outer space etc.?