I'm trying to install pi-hole on a new Raspbian 3 device with Raspbian GNU/Linux 9 with the command:
curl -sSL https://install.pi-hole.net | sudo bash -x
It shows a blue dialog window, but that only show a few seconds and it ends with:
The following packages have unmet dependencies:
dialog : Depends: libncursesw5 (>= 5.6+20070908) but it is not going to be installed
libtinfo5 : Breaks: dialog (< 1.2-20130523) but 1.1-20120215-2 is to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
So the wheezy is gone and I replaced it with stretch. After that the update and upgrade commands worked without errors and after that the installation of Pi-Hole went without any problems.
I dont know why Raspbian has Stretch packages available on the archive.raspbian.org and the mirrordirector.raspbian.org location.
But why not copy the whole (default) line from my sources config file including the "rpi" packages ?
deb http://mirrordirector.raspbian.org/raspbian/ stretch main contrib non-free rpi
EDIT: Weird thing is, they even did not bother to deploy new way of apt (Version>=1.1) selecting mirrors:
I went with your comment that wheezy shouldn't be in my sources.list file. If I did an install and upgrade command sequence I got a whole bunch of 403 Forbidden errors. I googled it and one suggestion was to change my sources.list file, that is how wheezy ended up in my sources.list file. That got rid of the 403 errors but introduced a whole bunch of other problems.
You made a comment that wheezy shouldn't be there. So I did a complete reinstall and this time only made minimal changes to the sources.list file and only changed the url part (not everything that is behind it). I did not even notice that in your version rpi is included. But (for me) it works without adding rpi.