For my notes, click my username and via private message send me one of the U2417H service tag number.

This is normal and within manufacturer specifications. All Dell monitor panels are uniquely calibrated at the factory to their own unique panel. No two panels are identical, even of the same model. The colors may not match but still be within manufacturer specifications. If you want a closer match, you will need to purchase calibration hardware (colorimeter) and software. Then calibrate both monitors.

The difference is big and very noticeable.  I bought the same product because of the quality, and got something else, worse. 

You suggest an expansive solution which is unacceptable.

I think that you do not understand what are manufacturer specs.

When they say "factory calibrated with (avg.) error under X dE (to some unknown target, presumed to be sRGB gamut and D65)" they mean exactly that (including uncertainties explained in parenthesis).
-If you have a sparse set of points and take average distance to some points... you'll get points far away that average distance "X" by definition. If those points further away from average error are in greyscale they will be very noticeable.
-They make no claims about uniformity across the screen.
-If that "unknown target" is panel native gamut (extended a few outside sRGB) unit to unit differences will be bigger, visually & quantitatively bigger.

If your second unit has much worse contrast that will be a reason to return it (for me).

If you want such levels of quality, buy a NEC EA series or better, and maybe an i1DisplayPro. Otherwise you will be playing with this kind of manufacturer "tolerances".

Regardless, I have stated the Dell policy. If purchased directly from Dell, you have 30 days from the Dell invoice date to return it for refund. If not purchased from Dell, contact the seller for their refund options.

Thanks for the reply.

When I open a white page the display looks a bit pink...