having a similar problem on a windows7 64 bit system. Worked fine on one machine but on the second i noticed the installation defaulkted to installing in C:/ program files whereas virtual technician installs in C:/ program files(x86). My suspicion is that Virtual technician is too dumb to work if the two are not in the same folder.
Chat support was useless and so I've uninstalled mcafee. perhaps someone else can prove the theory