the first thing to try is disabling your anti virus program temporarily those things can block installation.
If that does not work please tell me what version of office you are installing
what operating system you are using
did you have another copy of office on the comuter
what is the exact complete word for word error message that you get at what point in the install ?
I have it working now but I would like to know how to backup the address book in Outlook 13, It was fairly simple in earlier versions. All the best.