If you installed Firefox before copying over the files, it's possible you have two "default" profiles, a new one and an old one, and the Profile Manager probably is only aware of the new one.

If that's the situation, you could try switching the names. For example:

Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Leaving that window open, switch back to Firefox and Exit, either:

• "3-bar" menu button > "power" button
• (menu bar) File > Exit

Pause while Firefox finishes its cleanup, then make a note of the random part of the current profile name.

Click "up" one level to the Profiles folder, and investigate its contents. It should have that folder you were just using, as well as the ones you copied in from your other system. If those other folders are not HERE, move them HERE before proceeding.

Right-click > Rename on the folder Firefox has been using. Make sure the entire name is selected, then press Ctrl+c to copy the name. Carefully add X at the end of the folder name and click away from the editing area to have Windows save the change.

Next, right-click > Rename on the folder you WANT Firefox to use. Make sure the entire name is select, then press Ctrl+v to paste the folder name that Firefox recognizes. Click away from the editing area so Windows saves the change.

Then start Firefox and you should be back in your old settings. Success?

Thank you for your help. I am writing this from my old computer. Your directions enabled me to put both the old version and the one I am trying to transfer together in the Profile folder. But neither one would display a profile. I must have done something else wrong because things have gotten worse. Now Firefox will not open, it opens a window which says, "Your Firefox cannot be loaded. It may be missing or inaccessible" I have titles of both data files on note pad and a complete copy of the files to be transferred on a thumb drive.

Sorry I messed up. Can you help me again.

Hi sloturner, one level up from the Profiles folder, in the Firefox folder, you will find a file named Profiles.ini. This is where Firefox is looking for the exact file names of your profile folders. So if renaming the folder didn't work, you can try editing the Profiles.ini file to match the folder name you have now.

If you do not see the .ini, that's normal, you can force Windows to show file extensions using the steps in this article: http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions.

Open Profiles.ini for editing by either double-clicking it or right-click > Edit. It usually opens in Notepad.

This file might contain only one profile, or it might contain multiple profiles. The one you need to fix is the one that has this line because this is the one Firefox is trying to use:

Default=1

In that group of lines, you will see a line starting with:

Path=Profiles/

The part after the / doesn't match reality, or in other words, you need to correct the part after the / to match the folder you want Firefox to start up with.

After making that edit, save the file but keep it open in case you need to make any corrections.

When you start Firefox, it should read the new information in Profiles.ini and start up using your old profile folder. If you get an error about the profile not being found, that usually indicates a typo (or paste error) in the Path.

If these semi-random names are too much of a pain, you can rename the profile folder to something of your choice like iLOVEpizza -- it doesn't really matter, the randomization is just for your protection against intruders trying to guess the folder name.