Hi Pete, thanks for your answer. I don't have the registered FSUIPC, it was installed by CS products that I have, then I will continue searching the forums. I've read many topics with the same problem in other forums, but no solution... PMDG and CS guys don't say nothing, except that their products are perfect. Is for this reason I hoped that this was the problem... but after your answer I know that the problem is another one, and more complex. If I can't find a solution, I believe that I will uninstall FSX, and all the addons I bought, and throw all to the garbage... and forget it forever. I'