Invalid access to memory - System::Internal::Strhlpr::UnicodeAssign

<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:
Invalid access to memory.

Stack trace:
(002F14D4) System::Internal::Strhlpr::UnicodeAssign
(007E08AA) C4799_0
(007E2912) ____ExceptionHandler
(007DF88C) __ExceptionHandler
(0008A61F) ntdll.dll
(00077E7A) ntdll.dll.KiUserExceptionDispatcher
(006806A6) TRemoteFileList::GetFullDirectory
(00680173) TRemoteFile::GetFullFileName
(00718A0D) TTerminal::CalculateFileSize
(007161B1) TTerminal::ProcessFiles
(00718CEC) TTerminal::CalculateFilesSize
(007241D5) TTerminal::CopyToLocal
(00675077) TDownloadQueueItem::DoExecute
(00672277) TTerminalItem::ProcessEvent
(00670728) TSignalThread::Execute
(0008269F) Userinterface::C21_0
(000128F2) KERNEL32.DLL.BaseThreadInitThunk
(00064DE1) ntdll.dll
(00064DA9) ntdll.dll

(002F14D4) System::Internal::Strhlpr::UnicodeAssign
(007E08AA) C4799_0
(007E2912) ____ExceptionHandler
(007DF88C) __ExceptionHandler
(0008A61F) ntdll.dll
(00077E7A) ntdll.dll.KiUserExceptionDispatcher
(006806A6) TRemoteFileList::GetFullDirectory
(00680173) TRemoteFile::GetFullFileName
(00718A0D) TTerminal::CalculateFileSize
(007161B1) TTerminal::ProcessFiles
(00718CEC) TTerminal::CalculateFilesSize
(007241D5) TTerminal::CopyToLocal
(00675077) TDownloadQueueItem::DoExecute
(00672277) TTerminalItem::ProcessEvent
(00670728) TSignalThread::Execute
(0008269F) Userinterface::C21_0
(000128F2) KERNEL32.DLL.BaseThreadInitThunk
(00064DE1) ntdll.dll
(00064DA9) ntdll.dll

(007E0F15) C4799_0
(007E24EF) _ReThrowException
%

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.

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.