virtualbox.org

hi, i have 2 vm in my vbox, vD for developing , vT for testing. and both of them have their own snapshots. today i have many files to transfer from vD to vT. To make it fast and easy i choose to mount T's disk directly onto vD. That's where the problem starts:

when both T and D are off, i reverted T as usual to the latest snapshot-T, open D's configuration page, added T's disk onto D's IDE controller. there is a light-blue round icon in front of it.

i booted D and cp new files into T's disk, shut down, detach the T's disk. When T is up. i found the changes are not there ???
so I opened the media manager and saw "assigned to snapshot-T" in disk T's tooltip. I guess that means i should revert T to snapshot-x, right? (later proved wrong)

After reverting, i can see no change. Hm, i must have messed sth up. what about deleting this vm and build a new one ? but that wouldn't work either. vbox said there is snapshot. and the snapshot manager said there is a "child hard disk" and refused to do anything. then I am stuck.

After reviewing my procedure, it seems that the files i copied from vD is stored in a new child disk created from my latest snapshort-T. but its hidden. I cant access/delete it in T's snapshot page.

My question is why vbox didnt change my current disk T but created a new one from its snapshot ? and how can i use this hidden disk or remove it ? Next time should i empty a VM's snapshots before mounting its disk ?
please help, thanks in advance.

great, after detaching T's disk from its vm, i found the [+] in front of the disk in the media manager. after deleting all its sub entries, and reattach it to vm T, i am able to delete snapshot-t.
but why would i delete my testing snapshot , itn't be part of the test ...