Hide device information pop-up on Galaxy S3

It seems your device is in Factory Mode. To exit from it manually:

1. Open file manager that can access root folder (e.g. Root Explorer, ES File Explorer)


2. Go to /efs/FactoryApp/


3. Open factorymode file as text file. Change the content to ON and save the file


4. Open keystr file as text file. Change the content to ON and save the file


5. Reboot the device

Alternatively:

1. Install Terminal Emulator


2. Type su



3. Type (or copy-paste)

   
   
   

   rm /efs/FactoryApp/keystr
   
   rm /efs/FactoryApp/factorymode
   
   echo -n ON >> /efs/FactoryApp/keystr
   
   echo -n ON >> /efs/FactoryApp/factorymode
   
   chown 1000.1000 /efs/FactoryApp/keystr
   
   chown 1000.1000 /efs/FactoryApp/factorymode
   
   chmod 0744 /efs/FactoryApp/keystr
   
   chmod 0744 /efs/FactoryApp/factorymode
   
   reboot
   
   

You can also exit factory mode and remove the annoying message without root, but it won't fix it:

1. Go to Settings > Application manager > All


2. Search Factory Test and "Clear data", "Clear cache"

Reference: ZiDroid - How to Exit Factory Mode for Samsung Galaxy Devices