Desktop icons keep disappearing?

Now I didn't know if this was the correct place to post this but I have a strange problem with my desktop icons in Windows 7 RC (build7100). Everytime i reboot the PC my desktop icons disappear, so i right click the desktop and go>view>show desktop icons but its already ticked. If i disable icons and re-enable them they come back but when i reboot they are gone again and sometimes when i close apps. If anyone could please shed some light on the problem it would be muchly appreciated.

Thanks
Samuel

This was a clean install on a fresh partition as im dual booting it with vista home premium on my laptop. I have been dual booting it for about a week and it started happening after about 2-3days but during this time it BSOD twice but that was my fault for installing an incompatible anti-virus application and i know have the leaked microsoft security essentials beta but before that i also tried kapersky for win7 technical preview and avg free (avg=fail). Apart from a few little problems i have had such as the desktop icons (not fixed yet), ati graphics drivers (fixed) and for some reason youtube wont load at all not even the home page it just loads for a while and then says connection has timed out. But youtube is the only page it does it on. Anyway back to the apart from section Win7 is the best ting that ever happened to my laptop. Even though it has pretty decent hardware vista was always a little slow to boot and always crashes and gives me other troubles but win7 is super quick takes about 30 seconds from booting and choosing win7 up until i get to a usable desktop, in vista its 1-3mins before i can even really click on anything. Anyway im trying that system scan you suggested so far its been going for bout 5mins and its at 61%

The scan just finished and it says: Windows Resource Protection did not find any integrity violations. Oh well i might just have to get use to it. Do you have any insight on why youtube wouldn't be loading? i tried IE8 and FireFox 3.1 and 3.5RC (what i currently use) and neither work, however if i boot into vista it loads youtube fine. I duno why, if you could please help or point me in the right direction please?

There may still be issues with the desktop, if the UAC is completely disabled.

Yes i installed the latest flash player. Its not just the videos themselves that wont load its the whole of the site. Not a single page of youtube will load not even ones with no videos on them. I have searched everywhere but cant find any info about it.

@davidtb
I do have UAC disabled as of today but that was only to install my graphics drivers and it was doing it before i turned UAC off

My desktop icons are gone after each reboot. I need to go in and click View / Show Desktop Icons every time. Does anybody have any insight as to why this is occurring? I have not changed anything or installing anything new - it just started happening out of the blue. Quite annoying...