I had the same problem with Kenwood, Vertex and HYT software when I bought my Windows 7 laptop.
After pulling out all of my hair for a week I talk to a few colleagues and was told to try Orcale VirtualBox.
I was able to load XP, Dos and FreeBSD on my windows 7 desktop.
Now I just start my laptop run VB
and select XP. XP boots and I can program any radio that uses windows software. Plus with dos install I can program with that too but I prefer DosBox for that since I can slow the PC down.
What's nice with both programs is that they are FREE.