Hyper-V Failed to Change State Error Code 32788

I have a Hyper-V machine running on a server with 20GB of RAM available (according to resource monitor).  When I try to start it with more than 4GB of RAM it fails with this error.  I tried creating a new VM, using a different VHD file, all create the same error.  Before I updated Hyper-V it used to report insufficient memory.  What am I missing?

Thanks!

Mike