The only and best place where you should get VCD is from the slysoft site. If its a government computer they may have put restriction into place that prevent you from installing anything. You could start by going into user management, disable "User Account Control" and try installing again.
I do NOT work for Slysoft. Please DO NOT pm or email me with problems you may have!
OS: Win 7 Ultimate X64 || MB: Asus P5Q-E || CPU: Intel Q9550 || CPU Cooler: CM Hyper 412 Slim || RAM: 8GB Corsair XMS2
GPU: Asus GTX 680 DirectCU II OC 2GB || Screen: Asus VG278 || HDD: 2x Samsung Spinpoint F1 1TB
Op. Drive 1: LG BH16NS40 || Op. Drive 2: LG BH10LS30 || Op. Drive 3: LG GH20NS10
TV: Panasonic TX-P42S20 || Blu-ray Player: Panasonic DMP-BD85 || Sound: Logitech Z-5500