hey guys sorry to hi jack this thread but i couldn't find any other threads about this problem. i have just recently bought a used sf3 tuner that is "unmarried" and has 4 unlocks left on it.
So heres my problem, for some reason it will not upload my trucks stock tune. so i thought ok maybe i need to update firmware. had to go through the hassle of not having the cd and finally downloaded the software online. went to plug the device into my computer it reads i have an 'unknown device' and i need to download the software for it? but i already have the sct program open...go to update or use anything on the sct program and an error msg pops up stating i need to plug in my device! im going a little crazy. any help on the subject would be great!

 

Don't know if you got an answer yet or not but it sounds like driver issues. Go to the SCT website and look at FAQ's about manually installing drivers. Hope this helps.

Chuck