Index: VirtualBox-5.0.18/src/VBox/Devices/Storage/DevLsiLogicSCSI.cpp
===================================================================
--- VirtualBox-5.0.18.orig/src/VBox/Devices/Storage/DevLsiLogicSCSI.cpp
+++ VirtualBox-5.0.18/src/VBox/Devices/Storage/DevLsiLogicSCSI.cpp
@@ -3889,7 +3889,7 @@ static DECLCALLBACK(int) lsilogicR3IsaIO
     else if (RT_FAILURE(rc))
         AssertMsgFailed(("Writing BIOS register failed %Rrc\n", rc));
 
-    return rc;
+    return VINF_SUCCESS;
 }
 
 /**