What should I do if I encounter an issue with firmware updates?
Refer to the available Help topics on the printer control panel by pressing the Help button. For more troubleshooting and configuration, visit www.hp.com/support/ljE42540MFP or www.hp.com/support/colorljE47528MFP for firmware updates, advanced web server settings, remote/mobile printing options.
From the official HP Laserjet Managed Mfp E42540 manual, page 8
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