<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 5.9.4

Error message:
Ошибка доступа к памяти.

Трассировка стека:
(004104A7) Dirview::TDirView::PathChanged
(00081D3F) ntdll.dll
(0006F8EA) ntdll.dll.KiUserExceptionDispatcher
(00415B15) Dirview::TDirView::ExecuteRootDirectory
(00037F69) TNonVisualDataModule::ExplorerActionsExecute
(003B5348) System::Actions::TContainedActionList::ExecuteAction
(0019C4C1) Vcl::Actnlist::TCustomAction::Execute
(0037322C) System::Classes::_18201
(0002C2B1) USER32.dll
(0000D885) USER32.dll
(0000D1DF) USER32.dll
(0000CF9B) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.