<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 5.14.5

Error message:
Invalid access to memory.

Stack trace:
(002A9FB3) System::Rtti::_16787
(00087D6F) ntdll.dll
(00073211) ntdll.dll.KiUserExceptionDispatcher
(0044A0A5) Tbxstatusbars::TTBXStatusPanel::
(0044A0A5) Tbxstatusbars::TTBXStatusPanel::
(0044A134) Tbxstatusbars::TTBXStatusPanel::
(0045C91E) Shdocvw_tlb::TInternetExplorerMedium::InvokeEvent
(00449E29) Tbxofficexptheme::initialization
(0024F1DF) Vcl::Comctrls::TTreeNode::SetSelected
(003A33B8) __tpdsc__ Winapi::Windows::_IMAGE_NT_HEADERS32
(000436C9) USER32.dll
(000250B7) USER32.dll
(00024209) USER32.dll
(00023FCB) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.