@sportmedirk: Thanks for your report.
I have sent you an email with a debug version of WinSCP to the address you have used to register on this forum.

<Try to describe precise steps that lead to the problem (where do you click, what keys do you press, what do you see, etc.)>
<If relevant, consider attaching a session log file or a screenshot)>

WinSCP 5.21.1

Error message:
Out of memory

Трассировка стека:
(0043A642)
(0043A642)
(00E4B3FF)
(00E4CBAB)
(00E4F561)
(000F4D7B)
(000F5684)
(000F5802)
(000F7350)
(000C29E4)
(000C1E18)
(0000268A)
(00FCEEF5)
(00066A9C)ntdll.dll
(00066A69)ntdll.dll

Status: unknown_rel_addr

I know how to reproduce the problem or the problem happens frequently enough. I wish to be contacted by the WinSCP team to help resolving the problem.