The Equation Editor feature is included on your Office CD, but
the feature might not get installed automatically if you choose a
"typical" installation. If you have Office XP, then you can
manually install the Equation Editor feature from your Office XP
CD as follows:
1. Click on Start | Control Panel | Add/Remove Programs |
Microsoft Office XP | Change | Add/Remove Features | Next.
2. Click on the + sign next to the categories "Microsoft
Office" and "Office Tools" to expand them.
3. Click on the little downward-pointing black triangle to
the left of "Equation Editor", and click on "Run all from My
Computer".
4. Click on Update.