after using Opera Mail for years, I'd like to switch to Thunderbird. To import the mails I tried using the "import export tool" as written here elsewere.
Unfortunately I doesn't work, as I quickly get a warning from the script. If I choose "continue", Thunderbird is not responding anymore (even if kept running for hours).
I wonder, if the problem might be the huge number of mbs files. It is over 70.000 files, stored in over 7000 folders. (This is around 15 years of emails.) I already tried running the tool only over an inner folder with less files in it, but with no sucess.
Do you have an idea, how I can proceed?