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Almost always a scanning problem on the sender's side, not a printing problem on yours. A page fed face-down, a scanner lid left open in a bright room, or a contrast setting cranked to maximum all produce the same symptom: a solid black page. Here is how to tell which one it is.
| What the sender did | What you receive | The fix |
|---|---|---|
| Fed the page face-down | Completely black page, sometimes with a faint edge of white | Ask the sender to flip the page and resend; nothing you can do on your end |
| Left the flatbed lid open in a bright room | Black page with a grey or washed-out patch | Close the lid, resend; the scanner was reading the room's light, not the page |
| Set contrast or density to maximum | Near-black page where text is barely visible as slightly-less-black shapes | Reset the machine's copy contrast to normal and resend |
| Scanner glass is filthy | Black page with streaks or bands running down it | Clean the glass with a soft cloth, resend |
| Faxed the blank back of a page | Plain white or very light grey page | Not a black-page problem at all; the sender faxed the wrong side |
Print something local: a copy, a test page, anything that never touched the phone line. If that prints fine, your printer is innocent and the black page arrived black. This distinction matters because nothing you do to your own machine, new toner, clean rollers, factory reset, will change what the sender's scanner already recorded. Faxes transmit the scanned image, flaws included.
One more check: if you receive faxes through an online service that delivers PDFs, open the file. A black page in the PDF confirms the problem happened at scan time. No amount of reprinting will recover text that was never captured.
This is the part that confuses people, because the blank side of the paper is white in real life. But the scanner is not photographing the paper: it is measuring reflected light. Fed face-down on a sheet-fed machine, the scanner reads the underside of the page pressed against a dark backing or the inside of the machine, and with no light bouncing back it records maximum darkness across the whole page. On a flatbed with the lid open, it reads the lit room behind the paper instead. Either way the sensor sees darkness, and darkness is what gets sent.
Be specific, because "your fax came out black" usually gets a shrug. Say: "The page arrived solid black, which means the scanner read the wrong side. Please check that the page is face-up in the feeder [or face-down on the glass, depending on the machine], that the contrast is set to normal, and resend." Most machines have a small diagram on the feeder showing which way the page faces, and it disagrees from one brand to another, which is exactly why this mistake is so common.
If the same sender keeps producing black pages, ask them to make a local copy first. A black copy proves the problem is in their scanner settings, and it saves you both another round of phone tag.
Yes: skip the scanner. When you fax through software or an online service, you upload a PDF or document file and it is transmitted as data, so there is no glass, no feeder, and no face-up-versus-face-down to get wrong. LetterAgent's fax flow works this way: you describe the fax to your AI assistant, approve the quoted total, and it is sent from the file, not from a scan. The black-page problem simply cannot happen.
Ready to fax it? Fax with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is sent.
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