note
grep
I have a feeling you are opening the file with your editor before you check the for spaces. My bet is your editor is set to change <code>tab</code> to 8 spaces and then you're saving the change.
<p>Look at the file with [http://gnuwin32.sourceforge.net/packages/hextools.htm|hexdump] before you do anything with it.
<!-- Node text goes above. Div tags should contain sig only -->
<div class="pmsig"><div class="pmsig-133383">
<p>
[id://133383|grep]
</div>
626309
626309