Is this an install from DVD or are you trying to update to 8.1 through the App Store?
Log files should be kept here: $Windows.~BT\sources\Panther or $Windows.~BT\sources\Rollback.
Perhaps this is caused by third pty virtualization. Ask support/forum your virtualization vendor.
However in my experience when I mount iso image that sits on c drive, the installation is faster than from DVD. I use Hyper-V. (In addition to this I use SSD disk.)
HTH
Milos
Hi,
Please make sure your ISO file is working fine and then follow this guide to check your operation:
http://www.hyper-v-mart.com/HowTo/Create_HyperV_Virtual_Machine.aspx
Please Note: Since the website is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.
Meanwhile, it's suggested you ask in Windows Server 2012 forum for more professional help.
https://social.technet.microsoft.com/Forums/windowsserver/en-US/home?forum=winserverhyperv
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