Why can't I backup and sync photos in the Google photo app?

[AC Question]

why i cant backup and sync photo in Google photo app?

it keeps saying unable to change account and sync always off

 

[promote_liberty]

Same problem... Any answers yet?

 

[FaiqT]

You just have to use an older version of the Play Services. Look at this post. I tried, and it worked.
https://plus.google.com/+ChrisKetchell/posts/HyTdquf45bL