I keep getting "Error retrieving server information. [RH-01]" in play store
This can be caused by an incompatible GApps package. If that is not the case (and you're sure you have the correct / supported GApps installed), do the following:
Open the "Google Play" application, press the home button to return
Go to Settings → Applications → Manage Applications
Select the tab "All", search for "Google Play Store" and tap to open.
Click "Clear cache"
Press "Stop"
Back to Settings → Applications → Manage Applications
Press "Google Services Framework"
Click "Clear Data"
Press "Stop"
Start "Google Play Store" and should give an error
Reboot the system. Once the device has rebooted Google Play Store should work. Wait a minute or two if you do not.
This will help if the corrupt cache is the cause of their problems (a corrupt cache could lead to strange error messages, etc.). If that does not help, you can try the same steps but including "Clear Data" for the application of playstore.