How do I delete Simsun font?

Dear all,
I encountered a complex problem.
A word file shows messy at my computer, while it shows normal at my colleague's.
I think it's caused by the font, so I want to copy the font from my colleague's computer to mine.
When I attempted to install the Simsun font, a message said I must unintall the existing font.
When I attempted to delete the font, it said some program was using this font.

I wrote a batch file to copy it:

Code:

@echo off
taskkill /f /im explorer.exe
ren %windir%\Fonts\Simsun.ttc Simsun.bak
copy D:\Simsun.ttc %windir%\Fonts
start explorer.exe
pause

The script was performed successfully, but this issue wasn't solved.
I didn't check the version of this font, I think it wasn't replaced in fact.

How can I delete the font?

Thanks in advance!

What do you mean by messy? Generally if Windows can't find a font it should default to a standard font, not output garbage.

Are both computers running Windows 7?
What version of Office does each computer have?
Is the document in .doc or .docx?

You wouldn't be trying to open the doc in notepad, would you?

Thank you, FuturDreamz.
In fact, the spacing between 2 lines in header is very large, but it's normal at other computers.
It's a windows XP machine with office 2007.
This file can be displayed normally both with Office 2007 and Office 2010.
The document is in .doc.
I didn't try to open that file in notepad. I think the contents have no issue because it's normal at other computer.

Let me try to save it in .docx format, and try it.

FuturDreamz said:

What do you mean by messy? Generally if Windows can't find a font it should default to a standard font, not output garbage.

Are both computers running Windows 7?
What version of Office does each computer have?
Is the document in .doc or .docx?

You wouldn't be trying to open the doc in notepad, would you?

I noticed that it shows Simsun at the normal computer, and shows Simsun (Body) at the fault computer.