is the PST set as the default profile of the outlook program. Is outlook set as your default mail program? Both must be true for import to work.

Thank you, Matt. No, Thunderbird is currently primary. I'll look to switch that. I don't know about the default profile of outlook, but I'll look for that if switching the default program doesn't do the trick.

I'm finding this difficult to figure out. New Win11 user here just up from Win7, so bear with me.

In Windows if I go to Settings-Apps-Default Apps I have:

Mail - shows as default for: -MS-Unistore-Email -Outlook Mail

Outlook - shows as default for: .eml, .msg, .pst, mailto and others. Outlook (slightly different icon) - shows as default for same.

I'm not sure what the difference is between the two Outlooks I show, but see picture. I unmarked the setting in Thunderbird to have it check to see if it's default.

But I still get the "no profile found" error in Thunderbird when I go to Import and select Import From Outlook.

Wasn't able to import from Outlook, but I worked around by using a third party converter to turn the PST file into mbox files, and then with the import/export extension in Thunderbird, I was able to import all of those folders into Thunderbird. So now I definitely want to make sure Thunderbird is default, and will be my email client going forward. Didn't like the new Outlook at all, even seeming to freeze sometimes necessitating ending the process in system tasks.

So now just need to work further on customizing Thunderbird!

I have this problem too, I have some .pst files ranging in size for 60MB to 27GB.

My files are in C:\Users\username\Documents\Outlook Files - is that the right location?

I'm not sure about mbox conversion, is there a particular tool that can be trusted?

I have this problem too, I have some .pst files ranging in size for 60MB to 27GB. My files are in C:\Users\username\Documents\Outlook Files - is that the right location? I'm not sure about mbox conversion, is there a particular tool that can be trusted?

The one I used is called Relief Jet Essentials and it worked very well. This link is for the freeware version, but you'll almost certainly need the full version. If I had to do over again, I'd have gone to this first rather than trying to mess with importing into Office Outlook and then trying to get from there to Thunderbird.

https://www.outlookfreeware.com/en/products/all/OutlookConvertPST2MBOX

Thanks for this agentalbert, I will check this app out.