Problem Installing 04_Dimension_Pro_1.5_Expansion_Packs

I'm having a problem Installing 04_Dimension_Pro_1.5_Expansion_Packs on Vista Premium 32.
 
The installation gets about 3/4 of the way thru then I receive and error of "Cannot create D:\Multisamples"
 
Well for sure it can't... there is no "D" drive.
 
Have tried several times to install, including from an external drive. No joy!
 
Thanx!