This problem occurs with no addons installed. FS9 runs and loads the flights fine before the update, hangs after installing it. And this is using the same airport KLDJ, same plane(default Cessna), and the same time and season for all the tests. I did delete the FS9 folder that fs9.cfg resides in each time. Is there another place where FS puts files?

Thats funny because if you installed FS9 and the SP1 using default setting, FS9 should load with default cessna at KSEA. Again there's somehting you're doing wrong because many others would have reported the hanging issue after installing the SP1. I asked that you list out the way you're installing FS9 and SP1. That way we can correct what you're doing wrong.

Yes, I know that the default flight is KSEA. However, I knew the problem occured at KLDJ, but not only KLDJ, from past installs, so I use that as my test airport to keep things consistant. John, thanks so much for the list of files, that really helped me out. I have been able, in the last few days to install the update manually, without the installer, and everything seems to be fine so far. I can't explain any of it, unless there is something in the installer that MY pc doesn't like. Anyway, for the time being, I have my simulator back!!!! Thanks to all for trying to help me out of this, I do really appreciate it!