Assuming that neither replacement jack is OEM, I would guess that the centre connection on the jack is the problem on both new jacks. The only other thing to try would be to find another known good working Dell OEM adapter and try that with the new jack.
Hey, I know this is an older laptop but I a co-worker really just wants this one working which is usually an easy fix.  However, it is having an odd issue.  Like most Dells of this time, the power jack is broken.  The middle section is fully missing leaving just the bare metal center.  It will make decent connection with both a Dell and aftermarket adapter plugged into it (not ideal) but the BIOS recognizes them both and will charge the battery with both as well. Here is the wierdness of this whole ordeal.  I ordered a replacement 5-pin jack for the system and hooked it up.  The system will power up but the BIOS reads the adapter as "Unknown" so it will not charge up the battery.  I ordered another jack from a different vendor and the same thing happens.  Just to ensure that one of the jacks did not damage the motherboard, I put the damaged jack back in the system and it works like it supposed to.  I also updated the BIOS as well just in case there was an issue with that but it did not make a difference.  Neither new jack works with the system but the damage one still will. So I have no idea where to go from here.  Are both of the jacks not wired right for the system to recognize in the system correctly?  Any thoughts about this?  
Very odd Inspirion 17R N7710 charging issue... help.