the import probably crashed a couple of weeks ago. outlook is good at freezing up, especially if it has issues with the PST file it is reading. I suggest you try again.

Thank you - this was the second of two attempts, looking now the folders "outlook import" and "outlook import 1" appear identical (having got no further than a few deleted items from some time ago), suggesting either that the second import did nothing (if cumulative) or both for some reason got to exactly the same stage. Looking again, though, the deleted folder contains a lot of emails from 4 days in 2020 which I can find neither in my Outlook deleted items (which mostly doesn't go back that far, apart from 1 item that hasn't transferred) not in my Outlook inbox. (Nor for that matter in webmail). So something very odd seems to be happening.

PS Around that time in 2020 I bought a new laptop and had to import the old pst file to Outlook, so it seems possible that it's found that old file somewhere. But if so I don't know where.

I will give it another go. Two questions if I may - firstly, does it make any difference whether Outlook is open or closed during the process? Secondly, do you have a rough idea of how long it should take, as there seems to be no way of telling whether the process or frozen or proceeding very slowly?

I've just had another go at this as you suggested. Having looked again, what Thunderbird seems to have done on the last attempt is (a) to have imported the couple of months' worth of emails I have stored in my online webmail account, and (b) imported a couple of pst files which date from when I changed my laptop. Seemingly nothing was imported from the main pst file.

I've attempted to focus down a bit on what I'm specifically trying to do, by temporarily removing the "legacy" pst files from my laptop (leaving the main, current one), and just asked Thunderbird to import Mail messages. 4 hours later, it still shows "Importing.... 0%", which based on your reply suggests that this isn't working. I'm going to leave it running for a while longer, but without any confidence that anything is going to happen.

As previously mentioned, the pst file I'm attempting to import is of size just under 5 GB. I note that here, there is a statement "Please note that the Import Tool will currently not support ZIP files larger than 2 GB". As far as I'm aware, the pst file I'm trying to import is not a zip file, and it looks like this may be to do with importing from another Thunderbird profile. To check, can the import from Outlook process cope with a 5 GB pst file?

And does it make any difference whether Outlook is running at the time (which it is at present)?

Hello,

I'm wondering if I'm not having the same issue. In my case the import process is stuck at 33% and never progressing. Is there a way to access some logs or debug mode to have a better understand what is going on?

I have retried several times. Also retried from scratch by deleting my thunderbird profile but no luck still stuck at 33% for ever and ever.

Any tips to look deeper into this are welcome.

happy to open a bug report if needed.

I've just had another go at this as you suggested. Having looked again, what Thunderbird seems to have done on the last attempt is (a) to have imported the couple of months' worth of emails I have stored in my online webmail account, and (b) imported a couple of pst files which date from when I changed my laptop. Seemingly nothing was imported from the main pst file. I've attempted to focus down a bit on what I'm specifically trying to do, by temporarily removing the "legacy" pst files from my laptop (leaving the main, current one), and just asked Thunderbird to import Mail messages. 4 hours later, it still shows "Importing.... 0%", which based on your reply suggests that this isn't working. I'm going to leave it running for a while longer, but without any confidence that anything is going to happen. As previously mentioned, the pst file I'm attempting to import is of size just under 5 GB. I note that here, there is a statement "Please note that the Import Tool will currently not support ZIP files larger than 2 GB". As far as I'm aware, the pst file I'm trying to import is not a zip file, and it looks like this may be to do with importing from another Thunderbird profile. To check, can the import from Outlook process cope with a 5 GB pst file? And does it make any difference whether Outlook is running at the time (which it is at present)?

The 2GB reference is about importing a Thunderbird backup - nothing to do with Outlook.

I've never heard anyone say running or not makes a difference. What did you find?