The most common "Google play package file is invalid" error is faced by many users. This errors can occur by many means. This error usually occurs when you download any application from the Play Store and try to install it. There are some ways by which you can fix this error, take a look at the below mentioned tips and do as directed.
Tip 1 for invalid package file in play store
'Clear data' and 'Clear cache'
Go to setting and then to application manager and choose Google Play store app and clear the data and cache and see if the error is resolved or not.
After the above fix download and install the app again.