Thanks for your report.
I have sent you an email with a debug version of WinSCP to address you have used to register on this forum.
Trying to transfer a file, error pops up.
WinSCP 5.6.3
Error message:
Error transferring file '<anyfile>'.
Invalid access to memory.
Stack trace:
[018A6B82] C4727_3
[018A8BEA] ____ExceptionHandler
[018A5B64] __ExceptionHandler
[7749B466] ntdll.dll
[7745012E] ntdll.dll.KiUserExceptionDispatcher
[016A0DF7] _ne_set_request_private
[016A1CE4] _ne_read_response_block
[016A225B] _ne_begin_request
[016A2854] _ne_request_dispatch
[0169EAA8] _ne_put
[017F23F9] TWebDAVFileSystem::Source
[017F1A13] TWebDAVFileSystem::SourceRobust
[017F181E] TWebDAVFileSystem::CopyToRemote
[017E7979] TTerminal::CopyToRemote
[0173C403] TUploadQueueItem::DoExecute
[01739BC7] TTerminalItem::ProcessEvent
[01738078] TSignalThread::Execute
[011526AF] Userinterface::C21_0
[76653388] kernel32.dll.BaseThreadInitThunk
[77479F70] ntdll.dll
[77479F40] ntdll.dll