Another victim
I feel your pain. I have the same issues where the drive letters keep changing and breaking links to external data drives. If Parallels is used for casual purposes: surf the internet and play games, these issues may not be seen. Use for serious work brings these issues front and center quickly.
I hope you are not also experiencing "Finder not responding" issues. Mac reliability has been extremely good for me until recently when this issue surfaced.
Last edited: Jan 16, 2013