problem with internet explorer

I am using Windows NT workstation 4.0 with service pack 3.0. The I.E version 3.0 has come with the OS package. Now when i try to upgrade this I.E to recent version, I am unable to do it. I get an error message saying that system has all the requirements, but even then it cannot install the recent version of IE. so i tried to change the service pack thinking that i may have some solution, but the system pack is also not getting upgarded. i tried many times, but useless. The version of IE i was trying was with 5.5. so please help me in this matter.