<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 6.3.5

Error message:
Accés no vàlid a memòria.

Traça de pila:
(00E2333A) __InitExceptBlockLDTC
(00E24572) C6612_0
(00E265DA) ____ExceptionHandler
(00E23394) __ExceptionHandler
(00098D8F) ntdll.dll
(000781B1) ntdll.dll.KiUserExceptionDispatcher
(00AFAA7E) GetNormalizedPath
(00AFAB7F) GetCanonicalPath
(00AFAC1F) IsPathToSameFile
(00088C4E) TGUIConfiguration::LoadData
(0007BB2A) TCustomWinConfiguration::LoadData
(000E6B0E) TWinConfiguration::LoadData
(00B153B8) TConfiguration::LoadFrom
(000E4FC1) TWinConfiguration::LoadFrom
(00B157C9) TConfiguration::Load
(00B288C9) CoreLoad
(00B28A1B) CoreInitialize
(00E222D5) __wstartup
(0006B0C9) ntdll.dll
(0006B04A) ntdll.dll

The problem happens rarely. I cannot reproduce it.

Thanks for your report.
I have sent you an email with a debug version of WinSCP to the address you have used to register on this forum.

Opened WinSCP, functioned normally. Left it open for a few hours in the background, doing nothing. Then, I tried to open a remote file, got the error. Tried different types of files (built-in or other viewers, small-large, etc.), all had same error. Closed connection and reopened WinSCP, same error. I can access local files fine.

WinSCP 5.9.5

Error message:
Invalid access to memory.

Stack trace:
(00865DD6) __InitExceptBlockLDTC
(0086700E) C5073_3
(00869076) ____ExceptionHandler
(00865E30) __ExceptionHandler
(0008519F) ntdll.dll
(000731B1) ntdll.dll.KiUserExceptionDispatcher
(0008D38A) TTerminalManager::OperationProgress
(007735E5) TTerminal::DoProgress
(00694EBF) TFileOperationProgressType::DoProgress
(00694C20) TFileOperationProgressType::Start
(007795F1) TTerminal::ProcessFiles
(0077C12E) TTerminal::CalculateFilesSize
(00787F29) TTerminal::CopyToLocal
(00011709) TCustomScpExplorerForm::TemporarilyDownloadFiles
(0001232D) TCustomScpExplorerForm::ExecuteFile
(00012912) TCustomScpExplorerForm::ExecuteFile
(00018156) TCustomScpExplorerForm::DoDirViewExecFile
(00017FF2) TCustomScpExplorerForm::DirViewExecFile
(004089F4) Customdirview::TCustomDirView::Execute
(00406402) Customdirview::TCustomDirView::DoExecute
(00406FCF) Customdirview::TCustomDirView::WMLButtonDblClk
(0024F2A9) Vcl::Controls::TWinControl::WndProc
(002931D7) Vcl::Comctrls::TCustomListView::WndProc
(0037326C) System::Classes::_18201
(00031B59) USER32.dll
(000240EE) USER32.dll
(00019EB2) USER32.dll.CallWindowProcW
(00057059) COMCTL32.DLL
(0005712E) COMCTL32.DLL
(00056EDC) COMCTL32.DLL
(00031B59) USER32.dll
(000240EE) USER32.dll
(00019EB2) USER32.dll.CallWindowProcW
(0042CA7F) Dragdrop::TDragDrop::WndMethod
(0037326C) System::Classes::_18201
(00031B59) USER32.dll
(000240EE) USER32.dll
(00023A7D) USER32.dll
(00

I know how to reproduce the problem or the problem happens frequently enough. I wish to be contacted by the WinSCP team to help resolving the problem.