I downgraded iTunes to 10.5.2 and now my iPad cannot sync

Question

I downdated my iTunes from 10.7 to 10.5.2 in an attempt to solve the homesharing problem with my ATV2.
I had to uninstall iTunes to do this, and during the re-install I was told that iTunes Library.itl was created by a later version, so I hid it.
Now iTunes has installed ok but I cannot sync my iPad because iTunes says my iPad is registered to a different computer.
How do I overcome this ? I presume it must be possible to start-over after a total system failure.

Answer 1

My colleagues and I have a similar type issue after upgrading from 10.9.1 to 10.9.2.
We all use mid-2011 Macbook Pro's and also use a sapphiretech Vid-2x displayport to dual DVI adapter.  This adapter essentially bonds two additional external displays into one large monitor.  i.e. two 24-inch displays now become "one" supporting 3840x1080 resolution.  The only caveat to using this adapter is that both monitors need to be of the same model.  There are no drivers needed to use this hardware adapter.
We don't have displayports per se, rather we use the thunderbolt port.  The Vid-2x adapters have worked fine for us from 10.7 - 10.9.1.
Since some of us upgraded to 10.9.2 we've all experienced the same issue in that the Mac no longer recognizes the Vid-2x as being capable of the proper 3840x1080 resolution we require.  The best we can get is 3200x1200.  Another interesting note is that there are at least three different model pairs of monitors being used by us (Samsung, Asus, Dell).