I had the same problem. You have to first run BF3 through Origin, which will open Battlelog. I discovered this as I was creating a reply here saying I had the same problem, following the post format of http://forums.veniceunleashed.net/viewt ... =40&t=8246
"Have you ran Battlefield 3 successfully via origin: YES/NO" - So I ran BF3 on Origin which opened Battlelog, then I opened vu.exe and it worked perfectly.
I didn't read I had to do this anywhere else, the instructions should be more clear about this in my opinion.