1603: Error Installing Microsoft .Net Framework

from what i know about the net framework its a custom rather than an express install. express meaning that its a necessary download and custom is an optional one. the latest version of net framework is 3.0. if you dont need to have it in your computer you can go to your control panel look under the microsoft listings and you should see net framework version 1.0, 2.0, or 3.0 hit the remove and it should be gone. i hope this helps you but if not im sure someone will give you more things to try.