Chyba přístupu do paměti

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WinSCP 6.3.7

Error message:
Chyba přístupu do paměti.

Stack trace:
(0043A8AB)
(000B046F) ntdll.dll
(0007AB0A) ntdll.dll.KiUserExceptionDispatcher
(0043C342)
(004A3D02)
(004A1F55)
(00226F7C)
(00036731) USER32.dll
(00024D78) USER32.dll
(00024205) USER32.dll
(00023D6B) USER32.dll.DispatchMessageW

(0043A8AB)
(000B046F) ntdll.dll
(0007AB0A) ntdll.dll.KiUserExceptionDispatcher
(0043C342)
(004A3D02)
(004A1F55)
(00226F7C)
(00036731) USER32.dll
(00024D78) USER32.dll
(00024205) USER32.dll
(00023D6B) USER32.dll.DispatchMessageW

Status: unknown_rel_addr

The problem happens rarely. I cannot reproduce it.