I have read as much of How does the Windows RENAME command interpret wildcards as I can understand, and still cannot decide if there is some wildcard combination you can use to make RENAME do this:
Old file names: abc001.txt, abc002.txt, abc003.txt, ... etc
New file names: demo_001.txt, demo_002.txt, demo_003.txt, ... etc
or: x001.txt, x002.txt, x003.txt, ... etc
or: file01.txt, file02.txt, file03.txt, ... etc
What I do know is that rename abc*.txt xyz*.txt will change all abc prefixes to xyz, but only because abc and xyz are of identical length. Is there a simple rename command which will cope with either a shorter or longer prefix... or do you have to use a batch process to carry out such renames?