Problem using search in windows explorer

Hi.
I have read a few posts already regarding this but none appear to be specific to the problem I have, or the solutions tried do not work.

When new, my HDD was partioned (C:&D:) 225gb ea (don't know why, thats how it was new!!)

up until recently, the search function worked fine.

now, the search function still works on C: but not on D:. as C: is mainly programmes and sysfiles i never search it, but D: is where all my stuff is stored.

Mighty frustrating! i haven't intentionally messed about with any of the search settings but i did have a windows update for messenger and live etc recently. might be coincedence, but it kinda ties in with the time scale.

help me obi-wan-kenobi's, your my only hope!

i have tried that and my D: drive is included. i have tried rebuilding the index, but to no avail.
its a feature i used a lot and its soooo frustrating for it not to work.
please see attached screenshot

any further suggestions from anyone will be appreciated

indexing has now completely rebuilt and this still isnt searching.
so frustrating!!

I use File Locator Lite (free) for searching.
Works great, easy to use, no indexing needed.
FileLocator Lite - Free File Searching Utility

thanks for all the info. was down to folder permissions. believe it or not, it was windows OWN help file that resolved it!!
somehow, SYSTEM had been removed from security tab in folder properties. added it back in and allowed permissions and all searcehes work now! weird and i dont know how it got turned off. if anyone is having same problem then let me know and i will talk you through it!