I have done lots of searching both here and google and I have not found a resolution or suggestion about how to solve a windows server upgrade problem. For starters, my entire VSphere environment is 5.1 - everything. I have successfully installed and have running Windows 2012 virtual servers that I installed from scratch, no problems. I have also been able to quite successfully do in place windows server upgrades on *physical* servers from either 2008 or 2008R2 servers to 2012 server, no issues there either. I have also used Converter to convert 2012 physical servers to virtuals, again no problems.
Now what I am trying to do, first as an experiment, is upgrade a 2008R2 *virtual* server to 2012. I give the guest access to the media, in this case a shared vhd that contains the installation media, login as an administrator, and click setup from the 2012 media.
Setup asks me if I want to upgrade or do a new, I choose upgrade. It then begins its 5-step process, finishing the first three steps with no erros. After successfully completing the steps 'copying installation files' 'collecting files, settings, etc.' and 'getting files ready for installation' it prompts for a reboot. Now I get into a 'blue screen of death' reboot loop, ending with the error HAL_INITIALIZATION_FAILURE. I have the option to go back to 2008 on the reboot, and if I choose to do that I'm back to normal.
I first thought the issue was the paravirtual scsi and vmxnet3 drivers, but I injected those drivers into the server 2012 media to no avail. Then I tried an '08R2 server with just the LSI Logic driver for scsi and the e1000 NIC, but ended with the same problem. Both the servers I tried upgrading are running version 7 of the toolkit. Everything I've read suggests 5.1 is compatible with 2012, and for the most part as long as I'm not upgrading a guest I see that it is. Any suggestions for something to try to get an upgrade to go? Thanks in advance.