<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 5.7.7

Error message:
Invalid%20access%20to%20memory.%0D%0A%0D%0AStack%20trace%3A%0D%0A%28002503EC%29%20Vcl%3A%3AComctrls%3A%3ATTreeNodes%3A%3AGetHandle%0D%0A%280008147F%29%20ntdll.dll%0D%0A%280006F02A%29%20ntdll.dll.KiUserExceptionDispatcher%0D%0A%28003DEB55%29%20Customdriveview%3A%3A_16443%0D%0A%28003DEB55%29%20Customdriveview%3A%3A_16443%0D%0A%28003DEB55%29%20Customdriveview%3A%3A_16443%0D%0A%28003DEB55%29%20Customdriveview%3A%3A_16443%0D%0A%28003DEB55%29%20Customdriveview%3A%3A_16443%0D%0A%28003DEB55%29%20Customdriveview%3A%3A_16443%0D%0A%28003DEBE4%29%20Customdriveview%3A%3ATCustomDriveView%3A%3AIterateSubTree%0D%0A%28003F02FF%29%20Driveview%3A%3ATDriveView%3A%3AValidateDirectoryEx%0D%0A%28003DE8B5%29%20Customdriveview%3A%3ATCustomDriveView%3A%3AValidateDirectory%0D%0A%28001F3137%29%20Vcl%3A%3AExtctrls%3A%3ATTimer%3A%3ATimer%0D%0A%280034059C%29%20System%3A%3AClasses%3A%3A_18201%0D%0A%280002C2B1%29%20USER32.dll%0D%0A%280000D885%29%20USER32.dll%0D%0A%280000D1DF%29%20USER32.dll%0D%0A%280000CF9B%29%20USER32.dll.DispatchMessageW

Status: not_matched

Stacktrace:
Stack trace:
(002503EC) Vcl::Comctrls::TTreeNodes::GetHandle
(0008147F) ntdll.dll
(0006F02A) ntdll.dll.KiUserExceptionDispatcher
(003DEB55) Customdriveview::_16443
(003DEB55) Customdriveview::_16443
(003DEB55) Customdriveview::_16443
(003DEB55) Customdriveview::_16443
(003DEB55) Customdriveview::_16443
(003DEB55) Customdriveview::_16443
(003DEBE4) Customdriveview::TCustomDriveView::IterateSubTree
(003F02FF) Driveview::TDriveView::ValidateDirectoryEx
(003DE8B5) Customdriveview::TCustomDriveView::ValidateDirectory
(001F3137) Vcl::Extctrls::TTimer::Timer
(0034059C) System::Classes::_18201
(0002C2B1) USER32.dll
(0000D885) USER32.dll
(0000D1DF) USER32.dll
(0000CF9B) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.