Programs missing after update.

[Stephen]

Ever since I installed the last update with the newest kernel.

My gCDemu program is gone. I have been using to mount play disk images 
for windows games on a virtual cd.

I've been trying to reinstall it and it keeps giving me errors

sudo add-apt-repository ppa:cdemu/ppa
sudo update
and it updates the list from the repository
when I
sudo apt-get install gcdemu

This is what happens

Reading package lists... Done
Building dependency tree
Reading state information... Done
Package gcdemu is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'gcdemu' has no installation candidate

I've tried to find a .deb file to install it, and I have also tried to 
compile the source file by following the instructions. Nothing seems to 
work.

Thanks in advance;
Stephen