A one-time payment consumer Office licence like Office 2019 can be used on one PC at a time, it is only volume licenses or the subscription based Microsoft 365 licenses that can be installed on all your PC's at the same time. Yes, you can later transfer an Office 2019 licence to another PC. 2 Enter your Office 2019 or Office 2016 product key, and then select Install this product instead. If your product key is new, follow the prompts to complete the redemption process. Office begins the update process. Close all Office apps to finish the process. None of the keys or the instructions work. SpUeH1.