<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 5.17.7

Error message:
Invalid access to memory.

Stack trace:
(004182C8) System::HandleAnyException
(00087E3F) ntdll.dll
(000732D1) ntdll.dll.KiUserExceptionDispatcher
(003A4BA8) System::Classes::_18201
(00043519) USER32.dll
(00024047) USER32.dll
(00023199) USER32.dll
(00022F7B) USER32.dll.DispatchMessageW

Status: all_insignificant

The problem happens rarely. I cannot reproduce it.