Can not install Office XP

Hi all,
I am supporting a laptop T40 IBM with windows XP professional. This user is just infected a lot of virus and adware because he is click on any ad that coming up. The OS is very update wity latest patches. Office 97 prof is installed.

The issue is, I try to install office XP to his laptop, the process goinng well untill 99% ( I guess) and then automatically roll back without any error message! I have tried myself 3 times, but I can not solve this issue.

I think if I reinstall the whole laptop with OS then the issue will be gone, but I still wonder if there is any way to fix it without reinstall this laptop or not.

Please kindly to advise me.
Thank you very much.
Quoc.