Separate installation.Use SysApp Pusher because you can't search those apps on the store.
What exactly does the error say and after what you do? Please provide a screenshot if possible.
Try checking if the date in your phone is correct. If it is, then change it to something like 2100 (or the maximum possible date) and restart the phone. After restarting try opening the app,it will give an error and the option to uninstall it.Uninstall it and change the date back to normal and restart. Now install again using sysApp Pusher.
