Sometimes there is problem with Play store in rooted smartphones. It is just stops working, either it says server Error or it says no connection. I recently had the problem and I managed to get rid of the problem.
There are many ways of doing so. Some options works for some while not for others. I will list all the possible ways that may work for you. You can try all options, see which one works for you the best.
- Restart your Smartphone. (Well if you came to this website that means you already tired and did not work but it is also a option.)
- Go to Settings>>Apps>>Play Store and clear the Data and Cache and try opening Play store again to see if it works.
- Change your Internet connection. I mean if you were using mobile network then change it to WiFi and the other way around. See if it works.
- As I am focusing on the problem in rooted phone then re flashing the Gapps is only the last option. Uninstall the Play Store before re flashing. I have not found any downside of doing so till now so I think you can reFlash it.
Note: If your Smartphone is rooted then probably you have CWM Recovery(or something similar) installed. I recommend you to back up your whole system and data. If some major problem appears than you can always restore.