Thanks Bill,for future questions I will visit the referals you proposed.After updating to FSX SDK SP1a and following the procedureeverything works fine.One other question: I was reading your system layout. Prettygood stuff. I'm battleing with frame rates and jerky simulation.My system: Windows xp sp2, FSX updated to SP1Pentium D 930(B1)3GHz, FSB 800MHz, DDR2 2048MB (533)267.3MHz,ATI X1300 AGP (8x)256MB, 160GB SATA Western Digital 7200rpm 8MB.In order to get frame rates of min 25 - 30 I have to reduce the scenery to low and no external traffic. No fun, just flying.Any suggestions?RegardsLutz Pansegrau, Cape Town