blaubar

What fixed it on a fresh install of Ubuntu20.04 was, as suggested by Paul above: Tools > Options > Integration > URL Overrides enable applicable schemes, FIREFOX in my case Note that I had never touched these options until now. Only ssh was enbled by default.

There are several quirks on the GUI that I think could be improved 1) "Path on server" requires a filename, so could read instead "Path on server with filename" 2) "Character set for backup" has the unfortunate default "7 bit swedish", what about "UTF-8"? 3) "Character set for backup" offers two, identically looking options "UTF-8". But they are not the same: the first is utf8, the second is utf8mb4. 4) When Default is selected the pull-down menu next to it can be changed. I suggest that the pull-down...

PCLoud causes exactly the same issue: 1) WIn32 won't start, 2) error " Faulting module path: C:\Windows\SYSTEM32\ntdll.dll", on WIn10. After removing PCloud all works.

Davmail cannot send mail larger than 1MB, timeout

Same problem with Thunderbird 31.4, Win7, Davmail 4.5.1-2303 Thunderbird settings...

Problem disappeared, mysteriously.

Repeated crashes on Win7 64biy