One solution was found.
---
function GetDefView:HWND;
var
Hdef:HWND;
begin
Hdef := FindWindow('Progman', nil);
result := FindWindowEx(Hdef,0,'SHELLDLL_DefView',nil);
end;
function GetDeskHandle:HWND;
begin
result := FindWindowEx(GetDefView,0,'SysListView32',nil);
end;
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