Is it possible you have some over-zealous security software that is preventing Vam from accessing the drive?
Have you tried creating a clean (empty) install of Vam? Create a new folder, like Vam.clean. The only thing you copy in there is the Keys folder with your license, and the Vam updater. Run the updater to complete the install, then load the default scene. If that's OK, then go to the hub and download something simple, like one hair preset with no dependencies. Apply that hair preset to the model in the default scene. If that's OK, then try downloading something still simple, but with a few dependencies, like a look with a demo scene. If any of these steps fail, then you have something wrong with your system, IMO.
If you pass those tests, then I would start copying vars from the main install to the clean install. Do it in groups. Divide the main install vars up alphabetically, ABC, DEF, and so on. After copying each group of vars into the clean install, beat the crap out of it looking for failures. Of course, some of the vars you copy will have dependencies. Let it download those and keep banging on it. At some point, you'll hit a group that causes the errors. Delete that group, and start feeding the group members back in one at a time, or in smaller groups. Divide and conquer, sweep for landmines.
