installing ut goty

Had to uninstall game of the year, and when trying
to reinstall it gets just about done installing and
I get this error

Critical error

Assertion FailedL:C>=2[File:..\..\Core\Inc\Fcodec.h]
[liner176]

Can anybody help me.

Thnx

It gets most of the way through the install and then
I get this error message:

Assertion FailedL:C>=2[File:..\..\Core\Inc\Fcodec.h]
[liner176]

Every time, sometimes its says [liner91]

System specs:

1 gig Amd T-bird 266fsb
Abit kt7a Raid Mother board
Creative Sound blaster live value
Panasonic 8x4x32 cd-rw
52x Delta Cdrom
64 meg Geforce 2 Ultra DDR
Amptron Ls17 Monitor
Windows 98se
Samsuung 40 gig hard drive
128 meg pc133 ecc ram w/ecc not supported

My cpu on this system used to be 1 gig Amd T-bird 200fsb and ut loaded fine, when i upgraded to a 266fsb processor my problem started. Ut goty would not load and i get this error above. But the old 400 version of ut would load????? Well, I set my new processor in bios as a 750 mhz 200fsb and the Ut goty loaded fine but lot's slower than I expected and lots slower than my 1 gig 200fsb. But besides that point Why will it not load on my 1 gig 266fsb????????????