Appreciate the post, had the same issue and searched in Google to see if I was alone. My experience differed however when it came to solutions. During the boot issues I just needed to hit Troubleshoot > Startup Repair, Windows was able to fix itself all 3 times it happened during my testing. After installing Vocalizer Pro 2(and not restarting) there was also no iLok entries visible in the services or add/remove section of Program Features however the tpkm.sys was inside the C:\Windows\System32\drivers folder. After running an iLok update(i tested fresh install and got same result) the installer actually removed tpkm.sys and it was no longer on my computer, at this point I restarted and had no issues.
Good luck everyone and thanks OP
