Looking to Fix Brother printer offline Open Printers and Devices windows from Control Panel. Again Right-click on the selected printer and click on “Set as default printer”. Under “Set as default printer” you can see your Printer status – offline or paused. If the Brother printer is paused, simply click on “Resume printing”.

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Some of the ways to fix the Brother Printer Offline error
Check Printer connection
Text the Printing Status
Check the Print Spooler service
Update Printer Driver
Run the Microsoft Fix it and check
Perform the troubleshooting steps and check
Try uninstalling and reinstalling the printer drivers and then, check
Please ensure that your Printer is set as default Printer
Regards,
Rachel Gomez