Thumb/flash drive in car, tips, problems?

I started this thread because I wasn't able to get my flash drive to play over the USB in my new car. I'm running a Maxell Maxdata 360 8 GB, in a Ford Focus with Sync. I got a message that says it won't run protected files.
The files I was trying to run were ripped to my computer from CD's, not downloaded. However I did download the track info and artwork for the CD's I loaded unto the thumb. I wonder if this was the problem?
I'm going to load my next thumb while offline and enter the info manually, maybe that will work. I'm also told to make sure the thumb isn't password protected, which it isn't as far as I know. I didn't set up a password and I think the default is for no password.
Any help or tips are appreciated.

What audio program do you use to rip your files?

Make sure your thumb drive is formatted to FAT32 or it cannot be read by a car usb. You can check by right clicking on the drive and looking at Properties.

Thanks. I'm using Windows media to rip the files. I've also seen the fat32 being an issue as I've browsed for info, so I'll have to make sure about that setting.
S.D. I can understand your attachment to vinyl, sometimes all this tech makes me pine for the old days.

Make sure you don't have Windows Media Player set to copy-protect your files when you are ripping.