People get the latest Windows version on their PC but the most recent version of Windows seems pretty hard for the beginners to operate. People often encounter this issue with HP Deskjet 2540 printer offline, which can be solved easily. You need to first check whether your router is working properly or not. Then see whether the wireless network is working properly on the printer and the computer also. Make sure your driver is compatible to the operating system and then check if the power cable is properly connected to the printer or not. If everything works fine but you are still getting the error, then try and restart your computer and then try to print. If your printer does not work in Mac, then there are different steps. Go to the Apple menu and then select your system preferences. Now, search for the printers and scanners option. Right click on the printer icon and click on remove the device. Next, follow the on-screen instructions to get it solved.