a weird problem on Font Courier New in MS Word

hi! In MS Word,font Courier New should have equal length on all letters, including space. But in my MS Word 2003, a space has shorter length than a letter or other characters. That happens to be a serious problem in my application where each column of text needs to be precisely aligned.

I suspect it's due to the Chinese Font I installed, but don't know how to fix the problem. Can anyone help?

I appreciate very much!