I recently solved a Fritz 13 installation problem, so thought it would be worth sharing the procedure. A Google search didn't help me out when I was wrestling with it, although it pointed out one Amazon.com review where someone had the same issue, so I knew I wasn't alone.
After getting a new laptop with Windows 7 - the previous one was running XP - of course the first thing on the list was to re-install my chess software. However, the Fritz 13 DVD refused to install. I would be able to get to the first autorun screen with the "install" button; however, the DVD would just spin after that and nothing would happen, other than my computer slowing down while it tried to process things.
Repeated tries, including running the Setup program on the DVD under different XP compatibility settings, didn't work, so I temporarily gave up. At one point canceling out of the install resulted in the error message: "The installer package could not be opened. Contact the application vendor to verify that this is a valid Windows installer package"
However, when re-installing some other software, during installation I received an error message that a file was allegedly missing; immediately afterwards, my McAfee security software said it had deleted a trojan. False detection errors can be a common error with security software during software installation, so I turned off McAfee and then successfully re-installed the other program.
Returning to Fritz 13, after two tries I was able to get it fully installed. To be safe, I ran the install in XP compatibility mode, but the key part was clearly disabling the McAfee security software. (On the XP installation, I had a different security program running.) If anyone else is having the same issue, hopefully the above will help.
EDIT: I put in a request for technical assistance at Chessbase.com and did in fact receive a response, although after I had resolved the issue. It reminded me that along with running Setup.exe in XP compatability mode, it might be necessary to run it as an administrator as well (which I had in fact attempted originally with no luck). Disabling the anti-virus software still appears to be the most critical step.