Sometimes mistakes happen; we're going to do, even in the services that seem to never go down. Although in reality it is not the first time that happens to Play Store, but hey, the fact is that you are not alone if you have problems or difficulties installing applications or surfing Play Store.
Many people, including us, is encountering problems when performing actions such as installing applications (either from the device or from the web), update or even navigate all the applications available on Google Play. We can see the codes RPC: S-7: AEC-0 or 941 among others, and it appears that the problem is on the roof of Google.
This means that we can only wait until the problem is fixed, since all the typical solutions that will often occur in the community have failed. And do not ever factory reset because you'll stay with factory applications and cannot install new from Play Store.
So the only solution that I can advise here is that you have patience, persistence and some also come evil without getting too silly (there are users who claim to try a second time work).