I just experienced a vmci.sys 0xc0000098 BSOD bluescreen on upgrading VMware Tools on Windows Server 2008 (not R2) and was stuck in an endless reboot loop. It would not even boot into safe mode. However, I used “Last Known Good Configuration” while booting up, and it fixed the issue and allowed me to boot into Windows. A quick Google search didn’t result anything similar so I figured I’d share my findings. Comment if it works for you!