Here is my suggestion

I would use a program like WinZip or 7Zip or WinRAR and zip up the BIAB folder on your C: drive (this is to make a quick backup in case something goes wrong. Do the same for the RealBand folder. Once you have a successful installation, you can delete these zip files, but if you have to get back to where you were, it makes sure you're not dead in the water. Why do this? Because, then you can safely install the new version (2015) on top of the old version. That way you make sure you keep any user styles or one-time-offer PGMusic styles and content (it happens), and any user created content that may be located in the BIAB folder currently.

You shouldn't neet to format the external drive. If you have downloaded or created any UserTracks, you want to make sure you keep them and they are located under the RealTracks folder.

So, when you get your 2015 hard drive, you should just be able to run the setup program on that drive and tell it that BIAB should be on the C: drive in the same folder as your 2014 setup. Also tell it that your RealTracks and RealDrums are on another folder and just point it to the external drive, so it uses the same folders as where RealTracks and RealDrums are currently located.

Let 'er rip and once done, you should have a functioning 2015 BIAB and RealBand setup. Once you are satisfied that everything works, you can delete the Zip files (or back them up to some other media, whatever makes you comfortable).

I don's see a need to reformat your external drive, however.

John

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