Locate c:\(yourname)\appdata\roaming and if there is a folder named Thunderbird' delete it. That is the place that all profile info is stored. Now, when TB starts, it will prompt for email account info and create a new profile. (And thanks for helping your dad.)

Thanks David. I couldn't find the file you mentioned, but my Dad's PC runs on Windows 7, so that's probably why!

It should be the same. However, you can start TB, click help>more troubleshooting information, scroll down to Profiles in left column, click about:profiles, click 'create profile' button near top of page. Enter DADSPROFILE and press finish. It should show on list of profiles on next screen. Click 'launch' button. It will then prompt him to enter his email information as it creates a new profile for him.

Thanks David. I'm glad you pointed me in that direction. It showed me what the issue is. My Dad's name is listed as the account holder but the URLs (or whatever they are) that identify the incoming and outgoing servers (POP, POP3 etc) are from an old email account that I closed down about five years ago! I tried to delete these entries but they won't delete.

Now that I think of it, when I first open TB it prompts me for the password from that old account, which I no longer recall. Looks like the PC just wants to hang on to the past!

I'm not sure where you stand now. Let's try this: rightclick on the TB icon on the PC's desktop and click 'properties'. The highlighted like is TARGET, showing something like c:\program files\thunderbird.exe Click on the line and add a space or two and then -p to the line and then click OK. Now, start TB and a panel will appear to select a profile. If you want to remove your old profile, you can delete it here. Its name is probably 'default user'. For your dad, click create profile, give it a name, and continue to finish. when done, it will continue to TB and he will be prompted to enter email account info. Let me know how this goes.

Thanks David. I did all that, but when it tried to open TB, I got a message saying that my profile "could not be loaded". I have uninstalled it again but I will reinstall it and have another try.

I appreciate all the time you spent trying to help me!

Okay, here's another approach. Open File Explorer. click to the root drive, probably the C: drive. scroll down the folders until you come to one called 'Users' - click that and look for a folder that may be a shorthand of your or your dad's name. There may be one called, Admin, one called Default, and one called Public. It's not any of those. Click the folder and look for a folder named AppData. Click it. Look for a folder called Roaming. Click it. Look for a folder called Thunderbird and delete it. That removes all profiles from the PC. It will all be gone. If you want to save it for any reason, then rename the Thunderbird folder to something else.

Now, install Thunderbird. It will find no profile, so the first time you start it, it will prompt to create a profile using your dad's email information. Let me know how it goes.

Thanks. There are three folders in the Users folder - Dell, Guest and Public. I opened them all and none of them has either my name or my Dad's name.

I honestly think I'm a lost cause, and you have already spent way too much of your time on me! It seems like my identity is deeply embedded in this PC, in a very entangled and confusing way & it just doesn't want to let me go!

Suzie, it may not have your or your dad's name, but usually is something unique to the account. Windows tries to set up basic account for the owner of PC. if the only ones were what you said, then it's probably Dell. look there for the folders I mentioned. I'm fairly sure they will be there. If so, proceed per other instructions above and let me know.

Hi David. I went through very single folder and file in Users, but found nothing. However, I then did a search of my whole computer for Roaming and Thunderbird, and I actually found them! I deleted Thunderbird, as you suggested, and the new version that I downloaded has forgotten all about me! My Dad is now the only ID.

Many, many thanks for your help. I was on the point of giving up!

Congratulations. I knew, working together, we could do it. Please mark this thread closed so that it will be removed from the open issues list. Your dad is a lucky man to have a daughter work so diligently for him. :)

I have done so (I hope!)

Many thanks again.