Has it ever run on this particular machine?

Have you attempted to transfer a profile from somewhere else such as your previous computer?

Thanks for helping. Originally (a month ago) the current version of TB was installed and worked on my new laptop. But I prefer the earlier version (31.8.0) which I tried to transfer from my old laptop, together with profiles, and I have not been able to get any to work since. What I would really like is to be able to use the earlier version again together with my old profile.

First of all I'd suggest you download the installer and install the older version from scratch, rather than trying to copy it over.

https://ftp.mozilla.org/pub/thunderbird/releases/31.8.0/win32/

But what's the problem with the newer version? I am always surprised at these sort of comments as I see very little change from version to version. Most cosmetic changes can be undone or overridden.

The error message means that part of your profile is in the wrong place, or the name doesn't match. The easiest way to fix this would be to start Thunderbird's profile manager and then point it to the transplanted profile.

http://kb.mozillazine.org/Profile_Manager

In fact I did not copy TB over, but tried to install the older version using the original s/w I had downloaded. As this did not work I downloaded a new current version which then came up with the error message of not being able to access or find the profile. It is true that, as a result of my extended efforts, there is probably more than one profile on the laptop. I think an added complication may be that the old and the new versions of TB seem to store 'profiles' in different parent folders. Perhaps the best would be to clean everything out and start again but, for some reason, I can't get uninstall to work and a search of 'thunderbird' reveals quite a scattering of files and folders, so I am uncertain how to clean up! Would erasing all files containing thunderbird related names be a possibility? Seems rather messy to me and probably ineffective. Your advice is much appreciated.

It seems to me that a complete clear out of TB would be best but, not being very experienced, I am nervous how to proceed since 'uninstall' doesn't work - presumably because of the multiplicity of TB files/profiles etc resulting from my failed attempts. Should I just proceed as in my previous message and delete everything that is obviously TB related or will I end up in trouble?

Close Thunderbird.

Go to C:\Users\<your username>\AppData\Roaming

Delete the folder named Thunderbird. (Or maybe it's Mozilla Thunderbird - I don't have Windows here to check against.)

If you can't see this folder then it is probably hidden. Go to the Organize option in your Windows Explorer and set it to reveal hidden files and folders.

Re-start THunderbird.

I have uninstalled/erased everything I can find that is related to TB or its profiles, including the Thunderbird folder, and then downloaded the latest version TB setup from Mozilla. However, when I run it I still get the message that it can't load or find my profile. What is going on and what am I doing wrong?

At long last I have partly succeeded in transferring my old profile to my new laptop. It seems that temporarily disabling my virus protection enabled the TB setup to work. However, there is still one major problem: although the main folders in my inbox/sent/deleted folders have all transferred, all their subfolders have vanished. The only difference I am aware of is that I am now using the latest version of TB setup on my new laptop rather than 38.1.0 which was on my old laptop. I very much hope there is a way of recovering the many lost folders or should I try reverting to the older TB version on my new laptop? Thanks for your help.

PS to the above: I also find that all emails unfiled in the current inbox post 10 October, 2016 are missing!

Yet More: In an effort to overcome this problem, I have now uninstalled version 45 of TB setup and replaced it with my original earlier version 38.1.0. However, when I now try to transfer my profile it stalls after about 10% with the error message 0x80070057. So it seems I can't even put my old setup on the new laptop. I really have no idea what to try next and do hope someone can help.