|The computer can not read your mind. You have to know what you want to rename even if it is a part of the name or even something that is in the folder. Other wise you have to ask the user a question as to the name.|
Can you provide one of these like a partial name...
ren New* Old*
The * means any folders that start with the name new so like NewFolder will be renamed OldFolder and so on.
Or if there is a file that will exist in the folder that we can find. Something.