Invalid access to memory - System::UnicodeString::IsDelimiter1

Below is the error message received when trying to download a zip file. Unable to download any zip files.

[img]

WinSCP 6.3.4

Error message:
Invalid access to memory.

Stack trace:
(002A3BEB) System::SysFreeMem
(00E22DAE) C6612_0
(00E24E16) ____ExceptionHandler
(00E21BD0) __ExceptionHandler
(00087FFF) ntdll.dll
(00074531) ntdll.dll.KiUserExceptionDispatcher
(00121913) System::UnicodeString::IsDelimiter1
(00B7F167) UnixIncludeTrailingBackslash
(00B890FE) TRemoteFileList::GetFullDirectory
(00B88B7C) TRemoteFile::GetFullFileName
(00B84FAD) TRemoteFile::Duplicate
(00B88F0E) TRemoteFileList::CloneStrings
(00011FB9) TCustomScpExplorerForm::ExecuteCopyMoveFileOperation
(00012B5C) TCustomScpExplorerForm::ExecuteFileOperation
(00012DD8) TCustomScpExplorerForm::ExecuteFileOperation
(00012F97) TCustomScpExplorerForm::ExecuteFileOperationCommand
(0001311E) TCustomScpExplorerForm::ExecuteCopyOperationCommand
(0004F981) TNonVisualDataModule

The problem happens rarely. I cannot reproduce it.