Hi there. What kind of computer are you using?

Your profile should be stored in your computer in your user folder. Look for; C:\Users\==<UserName>==\AppData\Roaming\Mozilla\Firefox\Profiles or something like that. What folders are listed?

What do I do if I can find this user file. At the moment I can't find it. Where do I find it

Forgot stay, I am using an Optima laptop

If you can't find the profile folder, let's do this;

Create a new profile. https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

Start Firefox. Is it working now? (Don't worry about the blank profile.)

Look on your desk top. Is there a folder called; Old Firefox?

Yes, there is a folder called 'old Firefox'. Thank you very much for helping me, by the way.

See:

• https://support.mozilla.org/kb/how-run-firefox-when-your-profile-missing-or-inacc

This is usually caused by a problem with the profiles.ini file and the profile marked as Default=1 in this file is no longer present on the hard drive.

• Windows: %AppData%\Mozilla\Firefox\
  C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\
• Linux: ~/.mozilla/firefox/
• Mac: ~/Library/Application Support/Firefox/

You can use one of these to make Firefox create/use a new default profile:

• Delete the profiles.ini file to force Firefox to create a new default profile
• Use the Profile Manager to create a new profile
• Use "Choose Folder" when you create a new profile to select the location of a lost profile and recover this profile

• http://kb.mozillazine.org/Profile_Manager
• https://support.mozilla.org/kb/Managing+profiles
• http://kb.mozillazine.org/Profile_folder_-_Firefox

It is possible to recover data from the "Old Firefox Data" folder, but be cautious not to copy corrupted files to avoid carrying over problems.

• https://support.mozilla.org/kb/Recovering+important+data+from+an+old+profile
• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox