reg add HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\HideDesktopIcons\NewStartPanel /v {20D04FE0-3AEA-1069-A2D8-08002B30309D} /t REG_DWORD /d 0 /f
reg add HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\HideDesktopIcons\ClassicStartMenu /v {20D04FE0-3AEA-1069-A2D8-08002B30309D} /t REG_DWORD /d 0 /f


or run:
rundll32.exe shell32.dll,Control_RunDLL desk.cpl,,0