DirectX error

I have a PC with Win98 SE (all updates for operating system up-to-date) that after installing update for directX (upgrading to directX ver 9.0a from 8.1)upon startup rec’d message DXDLLREG has caused an invalid page fault in Kernel32. I’ve tried theupdate again and it still gave same error on startup. The directX won’t work. All drivers current- – video card is ATI Xpert 128 and sound built in on motherboard with ESS1879. DXdiag won’t start as gives messages can’t display video and sound info, probably due to install gone bad. Thinking of downloading redistributable 9.0a for full reinstall, but not sure if this will work. Any ideas?