Really this should be on the Adobe support forums but they have marked the issue as closed and I can’t attach a comment.
On a fresh Windows 8 install, I found that I could not install Adobe’s Creative Cloud services because Adobe Application Manager would fail during its install with a nebulous “A12E1” error code. After examining the logs it became clear that the application manager though there was an existing copy already installed in a “corrupted state”. This version was installed in the “Program Files(x86)\Common Files\Adobe\OOBE\PDApp” directory. I removed this directory in its entirety (after snapshotting my VM state) and then ran the install without any problems.
No promises here but if you are trying to install Adobe Creative Cloud on a fresh Windows 8 install and you are seeing the A12E1 error then this fix might help you out. I’m hoping Google magically brings those troubled by this problem here since A12E1 is a pretty unique search phrase. Good luck and safe travels.