Hi, Am new here; here goes. Am on Windows 7, 64 bit machine. A fast machine. Is it OK to run more than one instance of ExifTool at the same time? Each would be started by a different .bat file. I want to do this because my big renaming run (maybe 2000+ images) is s-l-o-w.
Yes, you can run more than one instance at a time.
But your renaming run shouldn't be slow on only 2,000 images. Are you executing exiftool in a loop? Make sure you aren't making Common Mistake #3 (http://www.exiftool.org/mistakes.html#M3). If you tell us how you're renaming, we might be able to speed it up for you.