It’s really a simple process applicable to all printer but ill take the specifics on how I did when my Brother Printer Offline status came up.
A few thoughts you can take some heed on.
Go to Start button -> Programs -> Devices and Printers . Then Right click the printer icon -> click see what’s printing. Remove check from Use printer offline. Make sure it is your default printer and restart your computer. It should be up and printing.
If you encounter quite seemingly similar issues, quick and reliable fixes are available in Brother Printer Offline support.