setup.exe is not a valid win32 applicati

I have a Athlon 900, 128Mb RAM 20Gb hdd, 32M 3D vid card, creative vibra sound card, Windows ME, CDRW RICHO 8X8X32.
When I go to install MS Office 2000 I get the above error “setup.exe is not a valid win32 application”
Has any body got any ideas, the CD works in a friends machine.