Why can't I install apps after reset?

[damarisjensen ackles]

I have a Lenovo A806 and I've reset my phone, everything seemed to be ok, but when I installed my old apps, like the backup app syncit and pinterest, It kept giving me "error -24" from google play. Then, I tried to download the apk file from browser and it was the same problem, saying "can't install the app". I kind of reached to the conclusion that I might need a system update because all my system apps needed update from 2014 version to 2017 version, but I do not have any software update or system update in my settings/about phone. Can anybody help me?

 

[makeev]

Are you sure that you have installed latest version of Google Play app?

 

[damarisjensen ackles]

Yes, I'm sure.