<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 5.13

Error message:
Acesso inválido à memória

Rastreamento de pilha:
(00703580) System::AnsiStringT<65001>::operator +
(00081D0F) ntdll.dll
(0006F88A) ntdll.dll.KiUserExceptionDispatcher
(0073B340) EncryptPassword
(0069CDB2) TConfiguration::EncryptPassword
(007526EB) TSessionData::EncryptPassword
(0075355F) TSessionData::SetPassword
(0081A8E5) TLoginDialog::SaveSession
(0081B2A9) TLoginDialog::GetSessionData
(003C0F10) System::Actions::TContainedActionList::UpdateAction
(001A6CA6) Vcl::Actnlist::TCustomAction::Update
(00218B0E) Vcl::Forms::_16777
(00218B0E) Vcl::Forms::_16777
(00218B8C) Vcl::Forms::TCustomForm::UpdateActions

The problem happens rarely. I cannot reproduce it.