Reboot the computer, see if that cancels out whatever is trying to use the file. When you come back, dont start up any other Intuit software, just log into your Intuit online account and download 2019.

Exactly did what you advised. Same error.

@Intuit_hieu   can you offer any advice on this error? It doesn't ring any bells for me.

@rollie Which windows version are you installing ProSeries 2019 on? The error is saying that the file is being used by another application on your machine. Do you have virus checker on your machine, would it possible you can whitelisting the ProSeries, and its installer?