Invalid access to memory - TLoginDialog::AddLoginButtonImage

<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 6.5.4

Error message:
Invalid access to memory.

Stack trace:
(00036E4E) apphelp.dll
(0008818F) ntdll.dll
(00074711) ntdll.dll.KiUserExceptionDispatcher
(00DAD19D) TLoginDialog::AddLoginButtonImage
(00DAC7E8) TLoginDialog::UpdateLoginButton
(00DB0592) TLoginDialog::ActionListUpdate
(00221920) System::Actions::TContainedActionList::UpdateAction
(0038ADA1) Vcl::Actnlist::TCustomAction::Update
(004ACF22) Vcl::Forms::_16859
(004ACF22) Vcl::Forms::_16859
(004ACF93) Vcl::Forms::TCustomForm::UpdateActions
(004B29EA) Vcl::Forms::TApplication::DoActionIdle
(004B1B9F) Vcl::Forms::TApplication::HandleMessage
(00DB0AD0) TLoginDialog::Execute
(00121243) GetLoginData
(000CE441) TTerminalManager::NewSession
(000252CC) TCustomScpExplorerForm::NeedSession
(0005B8BF) TScpCommanderForm::NeedSession
(00025244) TCustomScpExplorerForm::LastTerminalClosed
(000CB0D3) TTerminalManager::FreeTerminal
(000CA38F) TTerminalManager::FreeActiveTerminal
(000CAE23) TTerminalManager::ReconnectActiveTerminal
(000E0B38) ShowExtendedExceptionEx
(000269DC) TCustomScpExplorerForm::ShowExtendedException
(000CC5E5) TTerminalManager::TerminalShowExtendedException
(00D35F08) TTerminal::ShowExtendedException
(004B2022) Vcl::Forms::TApplication::HandleException
(00204C90) System::Classes::_18364
(00040459) USER32.dll
(00036B45) USER32.dll
(000353EB) USER32.dll
(00034F1B) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.

<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 6.5.5

Error message:
Invalid access to memory.

Stack trace:
(00064ECE) apphelp.dll
(000AEA5F) ntdll.dll
(00079A4A) ntdll.dll.KiUserExceptionDispatcher
(00DAD505) TLoginDialog::AddLoginButtonImage
(00DACB50) TLoginDialog::UpdateLoginButton
(00DB08FA) TLoginDialog::ActionListUpdate
(00221920) System::Actions::TContainedActionList::UpdateAction
(0038ADA1) Vcl::Actnlist::TCustomAction::Update
(004ACF22) Vcl::Forms::_16859
(004ACF22) Vcl::Forms::_16859
(004ACF93) Vcl::Forms::TCustomForm::UpdateActions
(004B29EA) Vcl::Forms::TApplication::DoActionIdle
(004B1B9F) Vcl::Forms::TApplication::HandleMessage
(00DB0E38) TLoginDialog::Execute
(00121243) GetLoginData
(000CE441) TTerminalManager::NewSession
(000252CC) TCustomScpExplorerForm::NeedSession
(0005B8BF) TScpCommanderForm::NeedSession
(0001CFBE) TCustomScpExplorerForm::ApplicationRestore
(004E307B) Vcl::Appevnts::TCustomApplicationEvents::DoRestore
(004B3C6D) Vcl::Forms::TApplication::InternalRestore
(00E06F8B) Vclcommon::C4884_0
(003A2A78) Vcl::Controls::TWinControl::MainWndProc
(00204C90) System::Classes::_18364
(00035231) USER32.dll
(000238D8) USER32.dll
(00022D65) USER32.dll
(000228CB) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.

<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 6.5.5

Error message:
Invalid access to memory.

Stack trace:
(00064ECE) apphelp.dll
(000AEA5F) ntdll.dll
(00079A4A) ntdll.dll.KiUserExceptionDispatcher
(00DAD505) TLoginDialog::AddLoginButtonImage
(00DACB50) TLoginDialog::UpdateLoginButton
(00DB08FA) TLoginDialog::ActionListUpdate
(00221920) System::Actions::TContainedActionList::UpdateAction
(0038ADA1) Vcl::Actnlist::TCustomAction::Update
(004ACF22) Vcl::Forms::_16859
(004ACF22) Vcl::Forms::_16859
(004ACF93) Vcl::Forms::TCustomForm::UpdateActions
(004B29EA) Vcl::Forms::TApplication::DoActionIdle
(004B1B9F) Vcl::Forms::TApplication::HandleMessage
(00DB0E38) TLoginDialog::Execute
(00121243) GetLoginData
(000CE441) TTerminalManager::NewSession
(000252CC) TCustomScpExplorerForm::NeedSession
(0005B8BF) TScpCommanderForm::NeedSession
(0001CFBE) TCustomScpExplorerForm::ApplicationRestore
(004E307B) Vcl::Appevnts::TCustomApplicationEvents::DoRestore
(004B3C6D) Vcl::Forms::TApplication::InternalRestore
(00E06F8B) Vclcommon::C4884_0
(003A2A78) Vcl::Controls::TWinControl::MainWndProc
(00204C90) System::Classes::_18364
(00035231) USER32.dll
(000238D8) USER32.dll
(00022D65) USER32.dll
(000228CB) USER32.dll.DispatchMessageW

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.

@mrckey999: 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.