Need some help. Just finished migrating from Exchange 2003 on a failing server to Exchange 2010 on a brand new Xen VM. All was well until it fell over possibly due to a failed disk on the new server. The Iscsi target was unattached on reconnection but after reconnection the VM was listed with only its D drive and no actual machine image, so I went back to an earlier snapshot and it was still not present, and back and back with still no VMI.
I got some help and we managed to reattach different images after we realised that the DVD drive had to have the same disk in as when the image was taken. We then went through mounting all of the images as the names of the images did not tell us when they were made until we found one that did work. This was a was a couple of days old so feeling confident we went to the next one as that must surely be the one required but is wouldn't load so we tried to go back to the one that did work except it was no longer there.
From an initial 6 images we had we now have only two showing but we haven't deleted them so where are they ? We had been renaming them as we went along so we knew what they were - might this have made them disappear?
The xen center offers few options and we don't know enough nix to go rooting around in the CLI . Really don't want to rebuild the exchange server but more importantly have severely lost faith in what we thought was our medium availability server configuration.
Is this normal for Xen of have I just really B*£$"D it up?

I cannot seem to find a good explanation of how Xen organises its images so is this ( most likely) my error or is this a common thing with Citrix.
How can I rescue my Images?
The exchange database is still present on a different Iscsi target- Can I make a new brand new VM load Exchange and and attach it to the old database?