Brother printers occasionally experience offline errors. So, this article tackles the causes of this error along with its solutions. We have detailed solutions for ?How to Fix Brother Printer Not Connecting Problem? for both Windows and Mac operating systems. Follow these steps to fix offline error: 1. Make sure your Brother printer is set as the default. If your Brother printer is not set as the default, you may have a problem with disabling the Brother printer. Follow the steps below to set the default printer.l When the Control Panel opens, click on Devices and Printers. in USA/Canada A list of the following printers will appear on the screen.device and printer From the displayed list of printers, right-click on the Brother printer and select the ?Set as default printer? option. standard set Now restart the printer to see if the offline mode issue is resolved.