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.
<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 5.6.3
Error message:
Error transferring file '\\HE111189e004\a644177$\Home\Data\aktuelles\2014\PD12-19\Zeitnachweise\Zeitnachweis 2014-12.pdf'.
Invalid access to memory.
Stack trace:
[011B6B82] C4727_3
[011B8BEA] ____ExceptionHandler
[011B5B64] __ExceptionHandler
[774771C6] ntdll.dll.RtlRaiseStatus
[77477052] ntdll.dll.KiUserExceptionDispatcher
[00FB0DF7] _ne_set_request_private
[00FB1CE4] _ne_read_response_block
[00FB225B] _ne_begin_request
[00FB2854] _ne_request_dispatch
[00FAEAA8] _ne_put
[011023F9] TWebDAVFileSystem::Source
[01101A13] TWebDAVFileSystem::SourceRobust
[0110181E] TWebDAVFileSystem::CopyToRemote
[010F7979] TTerminal::CopyToRemote
[009ECFCE] TCustomScpExplorerForm::ExecuteFileOperation
[009FDD17] TCustomScpExplorerForm::RemoteFileControlDragDropFileOperation
[009FDEA2] TCustomScpExplorerForm::RemoteFileControlDDFileOperation
[00FF24E4] TUnixDirView::PerformItemDragDropOperation
[00DB8DEE] Customdirview::TCustomDirView::DDProcessDropped
[00DDE8EB] Dragdrop::TDragDrop::WndMethod
[00D1F9BC] System::Classes::_18201
[75ECC4E4] USER32.dll
[75ECC5E2] USER32.dll
[75ECCC14] USER32.dll
[75ECCC6B] USER32.dll.DispatchMessageW