Formato carta non supportato

[Ketty2]

 al momento della stampa strasporta in foglio per metà e si blocca poi compare una spia rossa vicino al simbolo della carta e nel PC compare "formato carta non supportato" pur avendo selezionato un classico A4 

[RodrigoB]

Hi Ketty2

Thank you for visiting our English HP Support Community. We advise you to post your question in English to insure a quick response for the Community.This can also help other users to take advantage of your post, in the case they have the same question.

Thank you for your understanding.

Regards,

[Ketty2]

Hello, the printer reports that the paper is not supported via a red light next to the "paper" button 

[Jay_G24]

Hi @Ketty2,

I'd like to help!

Let's try a power reset on the printer

Reset the product

• With the printer turned on, disconnect the power cord from the rear of the printer.
• Unplug the power cord from the wall outlet.
• Wait at least 60 seconds.
• Plug the power cord back into the wall outlet.
• Reconnect the power cord to the printer.
• Turn the printer on. HP recommends plugging the printer directly into a wall outlet.

 update  printer's firmware - HP Printers - Updating or Upgrading Printer Firmware 

Also, try the steps in the document - Blinking Lights

Hope this helps! Keep me posted. 

And, Welcome to the HP Support Community. 

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