Hi@OH1973, Welcome to the HP Support Community I would be happy to help you with your HpPro MFP m479DW printer. I understand that you are unable to print photos on the A5 page and you have already done some preliminary troubleshooting.
Don't worry though as I have a few steps to determine the issue and find a solution as well,
Adjust the paper size setting:
- In the program, you want to print from, click File, and then click Print.
- Make sure your printer is in the Name or Printers drop-down list box, and then click Properties, Printer Properties, or Preferences.
- Click the Paper/Quality tab.
- Click Advanced, if necessary, and then click Paper Size.
Figure : Selecting the correct paper size

- Select the paper size that matches the size and type of paper loaded in the printer tray, and then click OK. If there are no matching paper sizes, select the size from the list that is closest to the size of the paper loaded in the tray.
- Click OK, and then try to print.
Check the paper source setting:
- Remove all the paper from all the printer input trays.
- Reload the paper, and then adjust the paper width guides so they gently rest against the edge of the paper stack.
- In the program, you want to print from click File and then click Print.
- Make sure your printer is in the Name or Printers drop-down list box, and then click Properties, Printer Properties or Preferences.
- Click the Paper/Quality tab, and then click Paper Source to select the correct tray.
- Click OK, and then try to print.
Click here and refer to the document to perform the above steps.
Keep me posted. Happy to help!
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