Hi, thank you for your reply, but when I try to access Settings -> Mobile networks, I get a message that says "Insert SIM card to access services"
As I stated in my original post, I don't have a SIM card in the phone yet, I'm trying to download via WiFi, so mobile network settings should in my (as of yet rather uninformed) opinion not be a problem.
I found out that the version of my Play Store app was 3.9.16.
I searched for the latest version and found out it's 3.9.17 (actually released yesterday). I downloaded the .apk from androidadvices.com, and installed it. Other than the version of my app now saying 3.9.17 instead of 3.9.16, no change.