Frequently Asked Questions

Several operators share this printer across shifts — who owns the cartridge swap?

Whoever runs the checks. Fitting this MICR cartridge (CE390X, the magnetic 90X) on the LaserJet Enterprise 600 M603n is a two-minute, tool-free exchange, so the standing rule in shift environments is simple: the operator who loads check stock also fits the MICR unit and logs the swap, and the next shift restores the standard cartridge.

What does the log actually prevent?

The two classic errors — a check run printed in standard toner, and a night of reports printed in MICR. A one-line entry (date, cartridge fitted, initials) makes the machine's current state knowable to everyone who walks up to it.

Remind me why checks need a special cartridge at all.

The line along the bottom of a check must be read magnetically by bank sorting equipment. MICR toner is magnetic; standard toner is not. The cartridge is otherwise the familiar CE390X format, rated at 24,000 pages.

Can any shift promise the bank will accept the output?

No one can promise that on a cartridge's behalf. Acceptance also turns on check stock, printer condition and the bank's readers. The site's validated setup — test checks on its own stock, confirmed by the bank — is what each shift is protecting when it follows the swap log.

Where should the MICR cartridge wait between runs?

Sealed in its box, labeled, in the supply cabinet nearest the M603N — not loose on a shelf where it can be mistaken for the standard unit or gather dust on the drum.

What cover comes with it?

A 1-year warranty and 1-year free returns. Help is available Monday through Friday, 9 AM to 5 PM CST.

About This M603N MICR Cartridge

This MICR cartridge (CE390X / 90X), at $194.41, serves the M603N that never really sleeps — a shared, networked machine where check printing is one shift's job among many. Rated at 24,000 pages, it ships from warehouses in IL, PA, GA and CA; the shipping & returns page sets out delivery and returns, and the rest of the range sits under HP.