<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:
Failed to delete tab at index 0

Trace de la pile :
(00249379) Vcl::Comctrls::_16736
(0024B333) Vcl::Comctrls::TPageControl::DeleteTab
(00019A58) TCustomScpExplorerForm::TerminalListChanged
(0000569A) TCustomScpExplorerForm::TerminalChanged
(000055A8) TCustomScpExplorerForm::SetTerminal
(000767B7) TTerminalManager::DoSetActiveTerminal
(00076742) TTerminalManager::SetActiveTerminal
(00075CEF) TTerminalManager::FreeActiveTerminal
(0001AB28) TCustomScpExplorerForm::ShowExtendedException
(00077BDD) TTerminalManager::TerminalShowExtendedException
(0070FC38) TTerminal::ShowExtendedException
(0034059C) System::Classes::_18201
(000374F1) USER32.dll
(00015C3B) USER32.dll
(0001553C) USER32.dll
(000152FB) USER32.dll.DispatchMessageW

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.

I use Remote Desktop Manager as a console for multiple different remote connection and WinSCP as a plugin.If the remote connection is terminated (i.e. the remote system is rebooted) whilst WinSCP has an open active connection, WinSCP goes into meltdown. Have not tried this so far outside for RDM

WinSCP 5.7.7

Error message:
Failed to delete tab at index 0

Stack trace:
(00249379) Vcl::Comctrls::_16736
(0024B333) Vcl::Comctrls::TPageControl::DeleteTab
(00019A58) TCustomScpExplorerForm::TerminalListChanged
(0000569A) TCustomScpExplorerForm::TerminalChanged
(000055A8) TCustomScpExplorerForm::SetTerminal
(00079289) TTerminalManager::TerminalReady
(00076114) TTerminalManager::ConnectActiveTerminal
(000769F4) TTerminalManager::DoSetActiveTerminal
(00076742) TTerminalManager::SetActiveTerminal
(00004FA9) TCustomScpExplorerForm::WMCopyData
(00004F13) __stdcall TCustomScpExplorerForm::HiddenWindowProc
(000374F1) USER32.dll
(00015C3B) USER32.dll
(0001581B) USER32.dll
(00066976) USER32.dll
(00077E54) ntdll.dll.KiUserCallbackDispatcher
(0001BD7A) USER32.dll.PeekMessageW
(001E088C) Vcl::Forms::TApplication::ProcessMessage
(000A9A85) Execute
(00002462) wWinMain
(007DEA01) C4667_0
(00064DE1) ntdll.dll
(00064DA9) ntdll.dll

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.