Is there a fix yet for this issue?

Hyper-v snapshot becomes unusable until you manually edit the corrupted xml after deleting a historical snap shot.

Easily reproducable.  Just delete a historical snap and the .xml gets extra characters resulting in the corrupted state of: Cannot access the data folder of the virtual machine

Work around:   Open xml and scroll to the bottom.   Remove any extra characters from the bottom of the xml.  Normally just one character (‘>’) at the end but can be an "echo"
of the last 1-30 characters.

Then restart the hyper-v and it works till you descide to delete another historical snap.

This issues has been happening for over a year and is reproducable.  Others have had the issue so I am suprised that it hasn’t been addressed yet. 

Same as locked issue:

http://social.technet.microsoft.com/Forums/en-US/windowsserver2008r2virtualization/thread/bed19854-e765-4ca3-accc-bbaf903c7f46/

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