How to Keep InDesign CC 2015 When You Install CC 2017
Here’s a quick tip/reminder that when you install InDesign CC 2017, whether it’s today, tomorrow, or six months from now, you have the option to keep CC 2015. But this option is somewhat hidden, and if you just click Update, the installer will also uninstall CC 2015.
Here’s the deal: In the Creative Cloud installer, click the Update button to start installing InDesign CC 2017. In the dialog box that pops up, click Advanced Options and deselect Remove old versions.
The same idea applies for other apps like Photoshop and Illustrator.