iPhone unable to print after connecting to printer

"iPhone unable to print after connecting to printer: I could print off my iphone at home and at work but it has stopped working? Iphone picks up the printer and goes through the settings to print, just doesnt do it? No VPN on iphone."

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Reinstall the Printer:

Remove the Printer from your iPhone, and then add it back. What is the Model of this printer? Who is the manufacture of this printer? AirPrint is the protocol of Apple, and you printer needs to have the compatibility (and it apparently does, being that it was working before).

Using a QR code:

So, does this printer have a screen on it? Some printers provide syncing through a QR code that is provided on the screen. You can download the installer from there, through taping on the iPhone's screen with the Camera app on. Tap on the QR Code when you see the yellow-highlighted back letters pop up on the screen.

This user has a solution --> Solution When IOS Devices Cannot See HP P… - Apple Community

Check the AirPrint settings in the Embedded Web Server (EWS). AirPrint uses Bonjour, Apple's zero-configuration networking, to automatically discover ...

Troubleshoot AirPrint issues

Extracted from the above HP link.

"Limitations and requirements when using AirPrint

You should be aware of the following limitations and requirements when using AirPrint:

• Bluetooth or 3G connections are not supported. AirPrint is compatible only via an 802.11 wireless network.
• AirPrint is a solution for Macintosh computers running Mac OS X 10.7 and newer. AirPrint is not compatible with OS X 10.6 or earlier versions.
• iOS AirPrint is a solution compatible with iOS 4.2 or newer, and Apple mobile devices iPad, iPhone 3GS or newer, and iPod Touch (third generation and newer) only.
• AirPrint is compatible only with printers released in 2010 and newer. AirPrint is not backwards compatible with any older printers, and there is no workaround to enable backwards compatibility with older printers.
• Any printer that is connected to the USB port of the Mac, PC, Airport Base Station, or Time Capsule is not supported.

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