I recently installed ArcPro to start playing around with the new functionality. Shortly after installing, I started noticing my python scripts failing that have run fine for years. After noticing that Python34 was installed with ArcPro, I renamed the Python34 folder and BINGO, scripts now function properly!
ArcPy uses the Python27 library so it was getting confused!
ArcPro users be aware!!
Jessica, it seems I may have a similar problem. What did you rename the Python34 folder to? I am trying to run ARCGIS 10.2 using Python27 and ArcPro on the same machine. How do I do that?