Saved word 2010 doc opens blank but size not 0kb

More precision is required in your explanation:

...when few of my users email word documents other users cannot open them...

Who are these few, these unhappy few, and who indeed are the others? In what form is who sending what to whom? As attachments to an email composed in WLM or from Word as an attachment? Are they being saved in a format that "some others" can't read as they have there program preferences set for a different program?

That you can open them as plain text files tells us that they are there, have you asked "the others" to try opening them in Notepad or Wordpad? Are they trying to open them from within their email programs, in which case their email may not be set up to open attachments.

Try writing something in both Notepad or Wordpad and sending them as attachments to emails, then we can see whether the problem lies with Word or the receipt of any email with a text attachment.

Silly thing, but it has happened, has the text colour in the Word document been reset to WHITE during transmission - Try dragging the cursor across the page as if you were going to cut and paste... If it highlights in blue then there is something there so reset the colour.

So it is an Office problem not an email problem - That tells us something, not sure what at the moment though!

What or which email programs are you using/are affected? Does it only happen with Live Mail? Have you tried it with others?