Odd Index Error, Could use a hand

[Scalemotorcars]

Ok about 10am today my forums index just up and blanked out to a white screen without any code changes at all. Rather then an error or even a timeout I get the download notice that my computer downloaded the index.php page to my computer. That's about 4 or 5 minutes after trying to get to the forum/index.php.

Here's a link if you want to try yourself. http://www.scalemotorcars.com/forum/


Now the odd part, all pages under the index, for example a sub forum or thread, those all work just fine. They load quickly without problems. All add on scripts like my Photopost all work exactly as they should. My CMPS homepage works just fine. = http://www.scalemotorcars.com

Here's what Ive tried unsuccessfully.

I thought It might be a code error on the index so I created a new style without a parent. When I try to load the new style I get the same white page and it doesn't actually change to the new default style. It just stays with my customs skin and I still get the blank page. I have not added any new products in weeks so I didn't think that was it but I disabled all and still no change. I changed the index permissions to 755 and even 777 to see is that made a difference but nothing. I removed all CMPS modules off the forum index with no change. I called my host but they have no error and no ideal what may have changed.

At this point Im out of idea's I know you guys get allot of "My sites broke" from newbies but Ive been at this for some time and this is a first for me.

Any thoughts would be greatly appreciated. Thanks.....

Daniel