diff --git a/setup/setup.nsi b/setup/setup.nsi
index 51ee767..68a27a7 100644
--- a/setup/setup.nsi
+++ b/setup/setup.nsi
@@ -511,6 +511,16 @@ Section "-un.Legacy Update Server" un.WUSERVER
 	${EndIf}
 SectionEnd
 
+Section "-un.Allow OS Upgrade" un.ALLOWOSUPGRADE
+	DeleteRegValue HKLM "${REGPATH_WUPOLICY}" "AllowOSUpgrade"
+	DeleteRegValue HKLM "${REGPATH_WUPOLICY}" "DisableOSUpgrade"
+	DeleteRegValue HKLM "${REGPATH_WUPOLICY}\OSUpgrade" "AllowOSUpgrade"
+	DeleteRegValue HKLM "${REGPATH_WUPOLICY}\OSUpgrade" "DisableOSUpgrade"
+	DeleteRegValue HKLM "${REGPATH_WU}\OSUpgrade" "AllowOSUpgrade"
+	DeleteRegValue HKLM "${REGPATH_WU}\OSUpgrade" "DisableOSUpgrade"
+	!insertmacro RestartWUAUService
+SectionEnd
+
 Section "-un.Legacy Update website" un.ACTIVEX
 	SetOutPath $INSTDIR