Got new HP Officejet Pro 8710 printer this January. While printing color pictures it puts several unprinted horizontal lines about a hairs width...

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Hi Karl,

Thank you for waiting!

Try getting into the Printer's Setting and Printer Maintenance,

Perform both Cleaning and Alignment at least twice.

And do another test print and see if there will be any difference.

I'll be waiting for your reply.

Hi Karl,

Tried calling your number.

Unfortunately got ino your voicemail.

I hope you can reply soon with the result or wheneveris the best time to reach your through your phone/

We'll be waiting for your reply 

Thanks

Ferdinand