A family of Microsoft relational database management systems designed for ease of use.
I had the same problem -- Access 2016 run-time on a Surface Tablet. I had two accounts on this computer, a local "admin" type account and a user account. It took twice as long top open Access DBs on the user account as it did the "admin" account.
I had locked down the user account pretty well. This included setting Internet Options to a fake proxy so that the user couldn't browse the Internet, only run Access apps. I decided to take out the fake proxy redirect. Bingo!!! The databases pops right up now. It seems that Access run-time is trying to "phone home" to do something. If it can't it keeps trying and then probably gives up and then DB app finally opens.