Corrupted Partition Table

[mufc99]

Let me just say that I love Virtual Box. I have used it for years. I have a question that I am not sure is related to VB at all. I am just trying to understand what is happening. My computer recently lost a partition and luckily I could get it back using TestdDisk.
I have VB running WIN 7 on WIN 7 host. I share some folders with full access. Now once in a while when trying to shut down VB it will hang on closing. It stays that way until using control/alt/delete. Not sure why it happens but is it possible that when this happens my partition table could get corrupted? The partition that disappears is shared with VB.
Thanks for any help or ideas.
Was quite pleased to be able to get back my partition but I am desperate to know how it could have happened. Quest for knowledge.

[noteirak]

The partition that disappears is shared with VB.

Do you mean you are using raw device mapping with vmdk? if yes, this is an expert feature, YOU should know what to do if you use it.
If that's not what you are using, please clarify.

Logs & guest config as described in Minimum information needed for assistancewould help.