David, I think I might have finally found one after trying about ten. The trial version converts about two minutes of the file so you can see how it works. I've tried two files and those have converted fine. I receive audio files as e-mail attachments and transcribe them. I have several companies I work with this way and the files are usually MP3, WAV, or WMA--even from this company. But for some reason that they can't even figure out some of their recordings are being saved with this .dat extension. (They play in WMP with the .dat extension, but not in my transcription software, which has a mile-long list of audio and video formats it DOES accept.)
Bob, I can't upload a sample file because all of these recordings have a lot of my client's customers' confidential info on them.
I was just getting extremely frustrated at trying so many that didn't work, wouldn't load, caused avast warnings, or wanted me to do the installation in the sandbox. This one isn't free, but under 20 bucks, which isn't bad. If nothing else entirely free works, I'll go with this one. (My only other choice is to play it in WMP and record it internally in another format, which is quite time consuming when you have several to do and will probably have more in the future.)
Thanks!
Pam