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Cannot reinstall Firefox because error message says profile is missing

Firefox 啟動失敗
SuMo Bot replied
Richard Voget
Richard Voget

I got so frustrated with not being able to reinstall Firefox because I kept getting the error message "Your Firefox profile cannot be loaded. It may be missing or inaccessible". So I deleted all the profiles after copying them to an external hard drive. Then I copied the file ending in.test from the Old Firefox data folder on my desktop to the AppData/Roaming/Mozilla/Firefox/ profile. Then I copied the biggest file ending in .default from the backed up Local profiles to the AppData/Local/Mozilla/Firefox/ profile. It doesn't matter if I delete or keep the Old Firefox data folder on my desktop, I still get the Profile Missing error message. What can I do, so my laptop would appear as if it had been powered up straight out of the box and never had Firefox initially installed or what do I do with my profiles to make them accessible?

I got so frustrated with not being able to reinstall Firefox because I kept getting the error message "Your Firefox profile cannot be loaded. It may be missing or inaccessible". So I deleted all the profiles after copying them to an external hard drive. Then I copied the file ending in.test from the Old Firefox data folder on my desktop to the AppData/Roaming/Mozilla/Firefox/ profile. Then I copied the biggest file ending in .default from the backed up Local profiles to the AppData/Local/Mozilla/Firefox/ profile. It doesn't matter if I delete or keep the Old Firefox data folder on my desktop, I still get the Profile Missing error message. What can I do, so my laptop would appear as if it had been powered up straight out of the box and never had Firefox initially installed or what do I do with my profiles to make them accessible?

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SuMo Bot
SuMo Bot

Hi.

As you have copied the profile do not copy anything back. Firefox will create a new profile.

Then you can take items from your old profile and put then in the new one to overwrite.

All this must be done with Firefox closed.

As you start of saying you can't install there is little logic as to why you want to reinstall.

An alternative option once you have a new install is to edit the profiles.ini to point to an older profile

Richard Voget
Richard Voget 提出問題者

Let me rephrase my dilemma, I couldn't open Firefox. I just got the the error message "Your Firefox profile cannot be loaded. It may be missing or inaccessible" So I uninstalled Firefox hoping I could start out fresh. But the installation quits midway and gives the same error message.

SuMo Bot
SuMo Bot

Hi.

It is possible the download is faulty.

However if you have a profile on Windows or your OS the install may well 'think' it's an update and try to keep your existing profile. Hence move your profile away from onto a separate drive/partition/sd card so you could recover data etc.

Delete Firefox completely before you try a fresh install

https://support.mozilla.org/en-US/kb/uninstall-firefox-from-your-computer

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