A family of Microsoft word processing software products for creating web, email, and print documents.
Had similar problem with Foxit Reader. Comment on CC clued me into checking CC. Open CC go to Performance Optimizer then click on Sleeping Programs. Check whether your software is listed under Sleeping Programs. If it is click on Wake Up. After I did that had no problem opening pdf file from Windows Explorers with Foxit Reader. Hope this works for you. CC has some interesting tools and capacities but can be aggravating at times.