That is an incredibly annoying bug. You can't paste a SINGLE word into Word without an error.
But there is a way around it...
1) Open Notepad.
2) Paste the text into Notepad.
3) Copy the text FROM Notepad.
4) Paste the text into Word.
_____
Anyway, you should download OpenOffice.
http://openoffice.org
It's a FREE office suite just like MS Office. Yes, free. And this isn't some trial- you can use it for as long as you want. And there's no nag screens!
It has:
• A word processor (like MS Word)
• A spreadsheet program (like MS Excel)
• A presentation program (like MS Powerpoint)
• A database management program (like MS Access)
• A vector graphics editor (like MS Visio)
• A mathematical formulae editor (like MS Equation Editor)
It is totally compatible with MS Office. It can even save in Office file formats!
Again, it's all free. And open source too! You might not even know what that means. But it's good.