Unable to scan slides/negatives.

[Geeba]

I am using Ulead v4 scanning software,but I am unable to scan slides/negatives.The manual says that I should pick positive or negative from the "Scan Source" menu,however these options are not available.There is just one setting which is "reflective" which works fine with photos/magazines.The web site says that there isn't an upgrade for the software,so I'm stuck.Can anyone help???