I've been plagued with a problem with my Brother networked laser printer (HL-2270DW). The printer keeps going offline, according to Windows 8.1.

Eventually I found the problem: The printer's IP address kept changing. I went to my router's admin, and specified that the printer's current IP address was reserved. This prevented the router from assigning that IP address to another device in the future.

Unfortunately this was not enough. Although the printer's IP address was reserved, it still kept changing. After downloading the "BRAdmin Light" utility from Brother I was able to configure the printer to use a static IP address:

Problem solved? So far so good...