For the benefit of anyone else who may ever encounter this problem ---Whilst playing around with the hardware settings( in the never ending quest for more fps)a small problem occurred.I was flying from Faaa(Fr polynesia ) with some addon scenery ,using the C195(Probably none of this is relevant but better the full picture.)After reseting the flight to check any changes in fps after altering some settings the load up stopped at 77%" Loading Weather".Thereafter ,in spite of poking all the settings around it refused to go past that point when starting up , either from closing FS or even after a complete system restart.The problem was eventually solved by deleting the FS9.cfg file and letting FS9 rebuild it- of course all settings reverted to default,but putting them back to where I was before I started the latest round of tweaking was OK. I've no idea what may have caused this - the hang was always at 77%Loading Weather.Just pleased to have sorted it.Any ideas on the cause welcome.My apologies if this has been mentioned before.

Dave,Not an answer, as such, but a reply nonetheless. I've had my sim load to 77% and lock up like you described. System locked up, so after reboot, I checked the event viewer which contained an event that involved a service startup at the time of the freeze. This has happened 3 or 4 times, and all coincided with a system service or virus program event. In any case, if it happens again, you might check your event viewer.Kevin

i believe that this is caused by not having the render to texture box checked when using the high performance DX..someting or other clouds. It's a knowed problem and i'm pretty sure it was mentioned in the cloud files read me.hope this helps.Callum.

Callum and Kevin Thanks for the replies- I'm pretty certain that "render to texture " may well have been the cause as that was among the things I had been altering when it happened.Whatever - all's well now.Dave