How do I configure my iPhone-6 and my Brother Printer MFC-J6510DW so that I can print directly (without activating my Computer Desktop) to print Photos and/or Documents?

the problem of your printer is sensor found on purge unit.

Brother offers a very good site about your error:

unless you see anything in the report that says, "incompatible ink" then there's nothing else to worry.

User guide http://download.brother.com/welcome/doc002835/cv_mfc6710dw_use_busr_lx7144001_b.pdf says either a mechanical problem or could be foreign object like paper clip or torn paper inside the machine. Open the scanner cover to check for that.

You may download software and drivers from here.

This may help others with scanning issues:
I just bought this and was nearly driven cracked trying to get the scanner to work as it was not talking to the PC, even though as a printer it was working fine. Realised eventually that it was just the Brother Control Centre 4 it wasn't talking to. After hours of re-installing software and updates, etc, nothing worked.
The solution: I went into Control Panel on my PC (I use Windows XP), to the Scanners and Cameras section, and in there the Brother Scanner was visible and could be used from there, Click on it to open the Windows Scanner and Camera Wizard and use that. Further, by right-clicking on it and going to properties I choose the software to start when it talks to the PC. I abandoned the Brother CC4 and set it up to start the Scanner and Camera Wizard if I choose 'Scan to Image' on the scanner control panel, and to open Photoshop if I 'Scan to File' on the scanner. Works fine either way, just make sure you choose the right dpi setting to suit your needs.
Hope this helps somebody else as frustrated as I was.

check if the noozles are on the catridges or on the independent print head. if the print head is seperate from catridges, them try print head cleaning. if you it cant work. then dip the print head in hot water for 5 to 10 seconds. dont dry it just put it back into the printer and try again immedeately. let me know if your problem is fixed

check cables, ink, and if computer reconize's it.

maybe is not configured to work with vista;s sorry.

We have multiple 7820s in our office. This would be a configuration problem with your windows XP computer. From the XP computer, open a command prompt and type "ping x.x.x.x" where x.x.x.x is the ip address of the 7820n. Make sure you get four successes. I would then uninstall the brother software and drivers and go to "printers and faxes" in the control panel and manually add the printer.

To manually add a network printer, with it's own print server, on Win XP:

1 Click "Add Printer"
2 Select "Local Printer Attached to this computer"
3 Deselect "Automatically detect and install my Plug and Play printer" then click "Next"
4. Click "Create a new port" and select "Standard TCP/IP" from the drop down. Click "Next". this will open TCP/IP Wizard
5. Type in Printer IP Address next to IP Address (Port name will autopopulate) and click "Next"
6. If wizard finds printer, it will show you "Finish" button. If you get a "Additional Port Information Required" window, something is wrong with your printer or windows xp network configuration.
7. When the TCP Wizard window closes, it will take you back to Add Printer Wizard. Select "Have Disk" and navigate to the \USA\WXP\Addprt directory on your Brother Drivers disc.
8. Select brxpadd.inf and click "Open" then click "OK"
9. Select "Brother MFC 7820 N Printer" from the list and click "Next"
10. Select name of printer, whether you want a default, print test page and DONE!