How can I install storyline to d drive, not c?

PERFORM. A. BACKUP. FIRST. I cannot stress that enough.

With drive space cheaper than water, and widely-available cloud storage from companies like Box and Dropbox, backing up your organization's intellectual property is not nearly as cost-prohibitive as it used to be. Add to that, with hard drive sizes as large as they have become, you have a LOT more to lose in the event of a drive failure.