Added kvm.rules, now my server won't boot

Hi all,
I've been trying to run a qemu for several days, and running into the error "qemu-system-x86_64: failed to initialize kvm: Permission denied". At first, I thought it was a simple permission error, but I'm in the kvm group.

I spent all morning reading through different forums and posts addressing this issue; In the end, I did the following:
1. I created "/etc/udev/rules.d/99-kvm.rules" with contents:
KERNEL=="kvm", GROUP="kvm", MODE="0660"
2. I restarted the libvirtd service -- systemctl restart libvirtd

Now, on the next reboot, the boot drive and filesystem aren't mounting. Do you have any recommendations?

Thank you for your time