Do two full or partly full cartridges need to be in place for the printer to work at all?

Hello, thank you for using Howly.
Do you see any error messages? Because if the printer requires two cartridges, then yep they need to be in place

Got you
No, your friend only needs a black ink cartridge. If he will print a color document in the future, then yes, the printer will have problems with it. But for black/white documents he needs only a black inc cartridge

It can be

You should try to use only a black inc cartridge. It depends on the model. In general, it should work with black inc only
What is the model of the printer?

Got you
Your friend can change settings to use only black ink. If he wants to print using only the
black ink or the color ink cartridge, he should follow the steps below.
1. Open the printer driver setup window.
2. Click Print Options... on the Page Setup tab.
3. Select the FINE cartridge to be used from Print With. And click OK.
4. When he will perform printing, the specified FINE cartridge will be used.
Also, the Black ink cartridge option can be named "Only PGBK (Black)"
You can use these instructions and check them. If you'll have any questions/ difficulties, you can always open this chat and contact Howly)

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