I'm having this errors when trying to install office.
How can I fix this?
Error 1923 can be a bit vague but was intended to mean that a previous version of office was found on the system and is creating a conflict. Here's the official MS solution:
To work around this issue, restart the computer after you remove the prerelease version of the 2007 Office programs.
However you may not actually have a previous version as there are a few of other things that can cause this, such as aggressive anti-virus or, as Matt pointed out, insufficient privileges.