virtualbox.org

Every time I use VirtualBox 4.1.20 I have to reinstall it first, because I keep getting missing kernel error on all my VM's
I'm using Mountain Lion, and running Windows 7 and Windows XP. However I made a simple VM with freeDOS and it does the same thing. Reinstalling fixes the problem until I close and restart VirtualBox.
Can I downgrade back to 4.1.18 without any trouble? I still have it in my download folder. Not sure if I can since I also have the 4.1.20 additions on both VM's.

Forgot to mention that I restart the machine (I bounce between OSX and Bootcamp). I boot OSX and when I try to start the VM's that's when the error occurs. I can open and close VM's as long as I don't restart OSX.

Try repairing the disk permissions using Disk Utility.

The short answer is yes, you can remove 4.1.20, and re-install 4.1.18 without any issues. Even if your guests are running 4.1.20 additions. I had to do this also, for some reason the 4.1.20 "upgrade" forced my mac to stop seeing an external monitor... Downgraded back to 4.1.18, everything returned to normal.