Nonprofit Technology Chat: microsoft office professional service pack 2. But I was completely surprised that nothing wrong happened to my system and how come this issue. Today the same thing happened with me also. If you are facing this problem you will not be able to run any of the MS Office applications. It happens to most of the Windows users when you try to open MS Excel or any other MS Office application and you get an error message “Installation Error: File not found” mostly skuo11.cab file not found.