Error after running VM once.

I just got a new Mac Pro, and I'm trying to use VB on it to use some linux distros. 6 GB of RAM, plenty of hard drive space, lots of processing power. Perfect for running VMs.
So I set up my virtual machine, set it up to install Ubuntu (I give it 256 MB of RAM, nothing too generous), and it runs and installs like a dream. Upon rebooting, I get an error:
Unknown error creating VM.
VBox status code: -32 (VERR_INTERNAL_ERROR).
Result Code: 0x80004005
Component: Console
Interface: IConsole {d5a1cbda-f5d7-4824-9afe-d640c94c7dcf}
This happens every time I run a VM from now on. It doesn't matter if it's a new VM, new VDI, or anything. It always happens. The only way to get rid of it is to reinstall VirtualBox... but even then, after the first run I get the same error.
So I have done some Googling and turned up empty-handed. If anyone can help resolve this problem, I'd appreciate it!

So I set up my virtual machine, set it up to install Ubuntu (I give it 256 MB of RAM, nothing too generous), and it runs and installs like a dream. Upon rebooting, I get an error:
Unknown error creating VM.
VBox status code: -32 (VERR_INTERNAL_ERROR).
Result Code: 0x80004005
Component: Console
Interface: IConsole {d5a1cbda-f5d7-4824-9afe-d640c94c7dcf}
This happens every time I run a VM from now on. It doesn't matter if it's a new VM, new VDI, or anything. It always happens. The only way to get rid of it is to reinstall VirtualBox... but even then, after the first run I get the same error.
So I have done some Googling and turned up empty-handed. If anyone can help resolve this problem, I'd appreciate it!

