If you open

%APPDATA%

using the Windows 7 Start menu search box, it should expand to the hidden folder:

C:\Users\your-user-name\AppData\Roaming\

Do you not find a Mozilla folder there?

Note: If the username in the Windows Explorer address bar doesn't match your usual, try shutting down and restarting Windows.

Can you bring up the Profile Manager by adding -P to the target line of the Firefox desktop shortcut?

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

Problem solved! Thanks for your help.

jscher2000 said

If you open %APPDATA% using the Windows 7 Start menu search box, it should expand to the hidden folder: C:\Users\your-user-name\AppData\Roaming\ Do you not find a Mozilla folder there? Note: If the username in the Windows Explorer address bar doesn't match your usual, try shutting down and restarting Windows.

Using your help and a bit of internet resources, I have solved the problem! Thanks!

altosoarus said

Following instructions on the support page, I searched for %APPDATA%\Mozilla\Firefox\Profiles\. Neither the Mozilla directory string or the file exists. As a result I cannot open Firefox.

cor-el said

Can you bring up the Profile Manager by adding -P to the target line of the Firefox desktop shortcut?

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

Problem solved, thanks for your help!