The obvious cause of brother printer saying its offline is because it is not set as the default printer on your computer. You can easily change the status of Brother MFC 5890 CN printer offline to online.  Under the devices section in your computer check, if it is listed as devices. You must re install the driver from the website. In case, you need to use the Brother Printer offline. Right click on the icon of Brother Printer machine. Then, see what’s printing and change it to offline.

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