Also, which I am guessing this is where the problem stems from...

I had to temporarily create a guest user on my computer for people to use my laptop while I was away for the day. When I did this, I downloaded Chrome and Firefox onto the GUEST account. So thats probably where this firefox being out of date issue is coming from (because I inadvertently downloaded a newer version onto the guest account than what I was running on my own account)

When I got home that day, I deleted that account and it was wiped. So I am back to just my own windows account, and have no way to back track. Any suggestions on how to revert to my previous version, or just transfer my bookmarks and such into the new version.

Cheers, James

Hi James, there is a command-line switch you can use when starting Firefox to unlock that profile so it can be used with an older version. This doesn't guarantee file compatibility if the newer version of Firefox converted internal formats/layouts of files. Whether that is a problem will depend on the gap between the two versions.

More info:

• Dedicated profiles per Firefox installation

Also, two different Windows accounts should not share the same profiles, so that's strange.

You can check the compatibility.ini in that profile to see what Firefox version last used this profile.

Firefox uses two locations for the Firefox profile folder, so make sure to look in the correct location. Location used for the main profile that keeps your personal data (Root Directory on about:profiles).

• C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\

"AppData" (XP: Application Data; Mac: ~/Library; Linux: ~/.mozilla) is a hidden folder. You can possibly use %AppData% (AppData\Roaming) in Windows File Explorer.

jamesdzimmer said

Also, which I am guessing this is where the problem stems from... I had to temporarily create a guest user on my computer for people to use my laptop while I was away for the day. When I did this, I downloaded Chrome and Firefox onto the GUEST account. So thats probably where this firefox being out of date issue is coming from (because I inadvertently downloaded a newer version onto the guest account than what I was running on my own account) When I got home that day, I deleted that account and it was wiped. So I am back to just my own windows account, and have no way to back track. Any suggestions on how to revert to my previous version, or just transfer my bookmarks and such into the new version. Cheers, James

jscher2000 said

Hi James, there is a command-line switch you can use when starting Firefox to unlock that profile so it can be used with an older version. This doesn't guarantee file compatibility if the newer version of Firefox converted internal formats/layouts of files. Whether that is a problem will depend on the gap between the two versions. More info:

• Dedicated profiles per Firefox installation

Also, two different Windows accounts should not share the same profiles, so that's strange.

Hey thanks for your help, I am slightly 'technically impaired' but understand some things.

From what I read from the links you provide, and any links within those articles, are you saying I should launch Firefox through the command line with the --allow-downgrade parameter?

When I try the route of changing the default profile, I get the same error message and am not able to use the old profile that came from the previous version of Firefox.

I also see the sync option. This seems like it might be the easiest to do, however since I am unable to access the profile that I need data from, I can't create an account within it to sync to this new version.

So I am somewhat lost. Would it be easier to downgrade to the a version under this new 67 version? Would that allow access to the older (original) profile?

And yes, I understand what you are saying about having a seperate microsoft user account shouldn't effect the apps or browsers on my administrator (main) account. So as to whether that was the cause, I am still not sure.

I apologize for taking up your time but appreciate any further insight you may offer.

Cheers, James

P.S. I see where to code in firefox -ProfileManager and then my next entry would be -allow-downgrade? Perhaps those are two different techniques, because I am not sure where to enter the allow downgrade command.

Hi James, you can temporarily modify your Firefox shortcut with the extra parameters.

First exit out of Firefox completely. Then, either:

• Right-click a Firefox desktop shortcut, then click Properties
• Right-click a Firefox icon pinned to the Taskbar then right-click Mozilla Firefox, then click Properties

Windows should show the Shortcut tab and select the Target field. The Target usually is along the following lines:

• "C:\Program Files\Mozilla Firefox\firefox.exe"
• "C:\Program Files (x86)\Mozilla Firefox\firefox.exe"

To add one or more command-line switches, make sure to type a space before the hyphen. For example:

"C:\Program Files\Mozilla Firefox\firefox.exe" -allow-downgrade -P

Does that let you pick the older profile? Please don't delete any profiles in the Profile Manager.

Hey jscher2000,

 That worked! I key'd in the additional parameter and when I opened firefox it had be select which profile, so I selected my older one and when it opened I had all my tabs and bookmarks. Thank you so much for saving this for me.

Now, the next question of mine. How do I go about saving my bookmarks so I can theoretically just download the newest version (or when some auto update runs and downloads it) I won't be in this predicament again. What is the easiest way to have my firefox data on a cloud or something so I can load them into a new profile.

My thought is that if I get these loaded into a profile that works with the newest version, it will probably be a few years until this would happen again. So I would rather be proactive and get it done now.

Thanks again for your help! James

Hi James, you can back up your entire profile folder from time to time. You also can create exports/backups of your bookmarks in a more convenient location from time to time. I'm sure there are other options.

• General backup: Back up and restore information in Firefox profiles
• Selective file recovery: Recovering important data from an old profile

• JSON-format bookmark backup: Restore bookmarks from backup or move them to another computer
• HTML-format bookmark export:
  • Export Firefox bookmarks to an HTML file to back up or transfer bookmarks
  • Import Bookmarks from an HTML file