HP LaserJet Pro 400 M401dw: Wi-Fi monochrome automatic duplex review

The HP LaserJet Pro 400 M401dw is an earlier monochrome printer for an office that wants automatic duplex and a choice of USB, wired Ethernet or built-in Wi-Fi. Its advantage over the wired-only variants is the included wireless network connection. The main limits are its print-only hardware, 300-sheet standard input and older software generation.

HP identifies the US model as CF285A#BGJ and explicitly marks it discontinued. Its 3.5-inch color touchscreen controls a black-document printer; it does not mean that the engine prints in color. The conclusions here come from the exact specifications and original instructions, without a new print-quality or speed test.

Choose a supported connection arrangement

The standard interfaces include a USB device connection, Gigabit Ethernet and 802.11b/g/n infrastructure Wi-Fi. The wired or wireless network arrangement can support Apple AirPrint as documented by HP. The phone or tablet and printer need the appropriate shared network, and the guide warns that firmware may need updating. Direct USB desktop printing is a separate arrangement and does not inherit network mobile printing.

The M401dw also documents an older feature called HP Wireless Direct. It lets a supported device connect to the printer without the office router, and the original guide describes an AirPrint route after enabling the feature. HP’s current explanation distinguishes that legacy connection from Wi-Fi Direct. Security behavior and simultaneous Internet access differ, so this review does not relabel it as Wi-Fi Direct or use it to satisfy that exact requirement in the finder.

Check a suitable current driver before connecting a modern computer. The original specification’s Windows XP/Vista/7 and early Mac OS X lists belong to its era. An old ePrint, web-application or automatic-install marketing claim is also not an assurance that every associated service or installer remains usable today.

Duplex output does not provide scanning

Automatic two-sided printing is included on the dw, with Letter, Legal and A4 supported in the original duplexer paper table. That is useful for reports and correspondence that would otherwise need a manual stack turn. It remains subject to the documented media limits; not every stock accepted in the multipurpose tray is eligible for duplex.

There is no flatbed, document feeder, integrated copier or fax. The actual front and rear hardware views describe printer components only, and the exact product function says print. Generic scan wording appearing in a family publication or menu illustration cannot add a scanner. If the daily routine begins with paper originals that must become files, choose a suitable multifunction model or separate scanner.

HP’s declared one-sided maximum is 35 Letter pages per minute, separately 33 A4 pages per minute. The ISO/IEC 24734 qualification excludes the first test set and notes variation with system and document complexity. These are not measured results here and should not become a 35-sheet-per-minute duplex promise.

Paper capacity and practical placement

The included 50-sheet Tray 1 and 250-sheet Tray 2 provide 300 sheets of ordinary plain-paper input. Both support Letter, Legal and A4 in the original table. The optional 500-sheet feeder expands a properly equipped unit but is not counted in the standard configuration. Confirm the actual trays when comparing an older offer.

Envelopes are supported through Tray 1 with suitable laser-compatible material and the correct size and type settings. The envelope rows have no duplexer check marks. Ordinary two-sided documents and occasional envelopes can be separate supported tasks without implying two-sided envelope feeding.

The unit body is listed at 14.35 inches wide, 14.49 deep and 10.67 high, with a 24.2-pound weight. Legal paper extends the main cassette behind it by about 2.75 inches. Raising the touchscreen, opening the multipurpose tray and reaching the supplies compartment need additional room; the closed dimensions are not a complete operating envelope.

Check the monthly routine and supplies

The recommended volume is 750–3,000 pages per month. HP separately lists a 50,000-page maximum duty figure. Evaluate the regular workload against the recommendation, while also considering the condition of an individual discontinued unit. A published maximum is not a present reliability guarantee.

The original package includes an HP 80A cartridge declared at approximately 2,700 pages. Replacement CF280A and CF280X declarations are about 2,700 and 6,900 pages under ISO/IEC 19752. Actual yield varies; these figures do not give current prices or remaining toner. Verify the US 110–127V rating label and demonstrate a real Wi-Fi duplex job before relying on an older example.

Choose the M401dw when monochrome network printing and automatic duplex are sufficient. A documented modern peer protocol, color output or scanning requirement points to a printer that explicitly supports that complete arrangement.