Why is Wine not installable on my system?

I've been having the same issue, it turns out that with newer versions of apt and dpkg they support a feature called "Multi-arch". In simple terms, you can specify that apt pulls package info from repositories for architectures other than the native install, and install multiarch compatible packages from those repos. For more detailed information, see: http://wiki.debian.org/Multiarch/HOWTO

Your issue specifically, is that the wine1.5-i386 is in the 32 bit wine repository, but not in the 64 bit repo, and your dpkg/apt are not configured to deal with this for some reason. To resolve:

Check your native architecture with:

sudo dpkg --print-architecture #in your case this should return 'amd64'

Other available architectures can be shown by:

sudo dpkg --print-foreign-architectures #in your case this should not return anything

So you need to configure a new foreign architecture (quantal/12.10 or newer***):

sudo dpkg --add-architecture i386

Check your new arch is now available, update and install your package with apt:

sudo dpkg --print-foreign-architectures #now this should return 'i386'
sudo apt-get update; sudo apt-get install wine1.5 #and away you go!

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***Note that the Ubuntu dpkg in natty (1.16.0~ubuntu7 (reports 1.15.8.10)), oneiric and precise (1.16.1.2ubuntu7) uses a different syntax:*

echo "foreign-architecture i386" > /etc/dpkg.cfg.d/architectures

Did you follow this procedure when installing wine :

open the terminal and type thes commands: but first remove wine by the command : sudo apt-get remove --purge wine*

sudo add-apt-repository ppa:ubuntu-wine

after adding the wine reprository which you already did. Using the software manager go to ‘edit’ and choose ‘software sources’. Select the ‘other software’ tab and click on ‘add’ at the bottom of the window. You now need to add the following line of code instead of the original Wine PPA link.

deb http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu precise main

You can now close the sources list and the software manager. Next to update your sources list open up the Terminal and type:

sudo apt-get update

Once your sources list has been updated you can install either the stable 1.4 Wine package or the 1.5 development package using the following commands:

Wine 1.4 (stable)

sudo apt-get install wine1.4

Wine 1.5 (development)

sudo apt-get install wine1.5

That’s all there is to it, you will now also continue to get the latest Wine releases and updates on your Linux, enjoy!

source of the solution

another solution: How do I resolve unmet dependencies after adding a PPA?

This is an error when trying to install the i386 package on a 64 bit install. try following this guide for your system!

http://wiki.winehq.org/WineOn64bit#head-77def7ca75193f24e358dba3dd6bcf674bd61b37

I know this because this is what I had originally done.