Access is Denied on vista

[DL13]

Hi guys, as my PC is down I finished building my second son's PC and I'm using it till mine is fixed, so as I'm trying to partition the hard drive I get this message ( Access is Denied ) the pic shows exactly what it is.

I did every thing I could think of, making sure I'm Administrator and every thing. I google it to and no luck. Can some one help?
Thanks.

[DL13]

Well, I figure out what I was doing wrong, I was trying to make the partition to big for the size of the hard drive I'm using. Oh well