Accès mémoire invalide - System::TMonitor::Destroy

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WinSCP 6.3.3

Error message:
Accès mémoire invalide.

Trace de la pile :
(002A6A35) System::TMonitor::Destroy
(00087FFF) ntdll.dll
(00074531) ntdll.dll.KiUserExceptionDispatcher
(00492DE9) Customdriveview::TCustomDriveView::CNNotify
(00409495) Vcl::Controls::TWinControl::WndProc
(0043F7E6) Vcl::Comctrls::TCustomTreeView::WndProc
(004095FB) Vcl::Controls::_17076
(00409495) Vcl::Controls::TWinControl::WndProc
(00408ADC) Vcl::Controls::TWinControl::MainWndProc
(002271BC) System::Classes::_18201
(000406E9) USER32.dll
(00036B35) USER32.dll
(00036735) USER32.dll
(0003AC0D) USER32.dll
(000744EB) ntdll.dll.KiUserCallbackDispatcher
(00034E38) USER32.dll.SendMessageW
(00068881) COMCTL32.DLL
(0003BF92) COMCTL32.DLL
(0003C09B) COMCTL32.DLL
(0003C09B) COMCTL32.DLL
(0003C09B) COMCTL32.DLL
(0003B9DB) COMCTL32.DLL
(0003EBC1) COMCTL32.DLL
(000406E9) USER32.dll
(00036B35) USER32.dll
(000362F1) USER32.dll.GetSystemMetricsForDpi
(00034B16) USER32.dll.CallWindowProcW
(004095A6) Vcl::Controls::TWinControl::DefaultHandler
(00409495) Vcl::Controls::TWinControl::WndProc
(0043F7E6) Vcl::Comctrls::TCustomTreeView::WndProc
(002271BC) System::Classes::_18201
(000406E9) USER32.dll
(00036B35) USER32.dll
(000362F1) USER32.dll.GetSystemMetricsForDpi
(00034B16) USER32.dll.CallWindowProcW
(004C32DF) Dragdrop::TDragDrop::WndMethod
(002271BC) System::Classes::_18201
(000406E9) USER32.dll
(00036B35) USER32.dll
(00036735) USER32.dll
(0003AC0D) USER32.dll
(000744EB) ntdll.dll.KiUserCallbackDispatcher
(00034E38) USER32.dll.SendMessageW
(0043C69D) Vcl::Comctrls::TTreeNodes::Clear
(00AEC77C) TCustomUnixDriveView::SetTerminal
(00AE9005) TUnixDirView::DoSetTerminal
(0005A19C) TScpCommanderForm::SessionChanged
(00008809) TCustomScpExplorerForm::DoSetManagedSession
(00008725) TCustomScpExplorerForm::SetManagedSession
(00006CB5) TCustomScpExplorerForm::~TCustomScpExplorerForm
(00058646) TScpCommanderForm::~TScpCommanderForm
(0011C16E) Execute
(000031E3) wWinMain
(00E200C1) __wstartup
(000670CC) ntdll.dll.RtlGetAppContainerNamedObjectPath
(00067099) ntdll.dll.RtlGetAppContainerNamedObjectPath

The problem happens rarely. I cannot reproduce it.