Dave,
Tools>Autocorrect>Autocorrect. Type ai9r in the replace
window and air in the with window. Click add, make sure
that replace text as you type is checked and click OK.
Repeat for other common errors
-----Original Message-----
How do I auto-correct words that have a number
inadvertently placed within the word, for example, ai9r
instead of air or blu3e instead of blue.