What happened to Android Market?
The venerable Android Market will be renamed the Google Play Store, while similar name changes will go into effect for Google's slew of playback apps — the Google Music app for example will now be called Google Play Music. Simple enough, right?
Does Android Market still work?
On June 30, 2017, Google will be ending support for the Android Market app on Android 2.1 Eclair and older devices. When this change happens, users on these devices will no longer be able to access, or install other apps from, the Android Market.
Why can't I log into my Play Store account?
Clear Data and Cache
Go back to Settings and Manage Apps just like before and then select Play Store and Play Store Services. Tap on Clear Data at the bottom of the screen and choose Clear Cache and then Clear all data. This might help you to sign in to your Google account again.