Stack trace:
(00241308) Vcl::Dialogs::TCustomFileDialog::GetItemName
(00087D6F) ntdll.dll
(00073211) ntdll.dll.KiUserExceptionDispatcher
(002413D4) Vcl::Dialogs::TCustomFileDialog::GetResults
(00240D0C) Vcl::Dialogs::TCustomFileDialog::Execute
(0023DFD9) Vcl::Dialogs::_16518
(0023EC76) Vcl::Dialogs::TOpenDialog::DoExecute
(0023EB2B) Vcl::Dialogs::TOpenDialog::Execute
(003FC38F) Comboedit::TCustomComboEdit::EditButtonClick
(0025BD51) Vcl::Controls::TWinControl::WndProc
(001C3EE0) Vcl::Stdctrls::TButtonControl::WndProc
(0025BEB7) Vcl::Controls::_17076
(0025BD51) Vcl::Controls::TWinControl::WndProc
(0025B398) Vcl::Controls::TWinControl::MainWndProc
(0038109C) System::Classes::_18201
(00043389) USER32.dll
(00023F87) USER32.dll
(00023B25) USER32.dll
(0002D0DD) USER32.dll
(000731CB) ntdll.dll.KiUserCallbackDispatcher
(000233FE) USER32.dll.SendMessageW
(00042B96) COMCTL32.dll
(0004F4DE) COMCTL32.dll
(00043389) USER32.dll
(00023F87) USER32.dll
(000234DA) USER32.dll.CallWindowProcW
(0025BE62) Vcl::Controls::TWinControl::DefaultHandler
(0025BD51) Vcl::Controls::TWinControl::WndProc
(001C3EE0) Vcl::Stdctrls::TButtonControl::WndProc
(0038109C) System::Classes::_18201
(00043389) USER32.dll
(00023F87) USER32.dll
(000230D9) USER32.dll
(00022EBB) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.