[TWTCommish]

You'll need to take out a few things.

In the registeradult template, replace this:

<tr>
	<td bgcolor="#13486D"><normalfont><b>Pop up a box when you receive a Private Message?</b></normalfont><br>
	<smallfont>This will pop up a small warning box when you receive a Private Message asking whether you want to view the message.</smallfont></td>
	<td bgcolor="#13486D"><normalfont>
		<input type="radio" name="pmpopup" value="yes"> yes
		<input type="radio" name="pmpopup" value="no" checked> no
	</normalfont></td>
</tr>

with this:

<input type="hidden" name="pmpopup" value="yes">

Next, open the registercoppa template, and replace this:

<tr>
	<td bgcolor="#13486D"><normalfont><b>Pop up a box when you receive a Private Message?</b></normalfont><br>
	<smallfont>This will pop up a small warning box when you receive a Private Message asking whether you want to view the message.</smallfont></td>
	<td bgcolor="#13486D"><normalfont>
		<input type="radio" name="pmpopup" value="yes"> yes
		<input type="radio" name="pmpopup" value="no" checked> no
	</normalfont></td>
</tr>

with this (yes, same as before):

<input type="hidden" name="pmpopup" value="yes">

Finally, in the modifyoptions template, replace this:

<tr>
	<td bgcolor="#13486D"><normalfont><b>Pop up a box when you receive a Message?</b></normalfont><br>
	<smallfont>This will pop up a small warning box when you receive a Message asking whether you want to view the message.</smallfont></td>
	<td bgcolor="#13486D"><normalfont>
		<input type="radio" name="pmpopup" $pmpopupchecked value="yes"> yes
		<input type="radio" name="pmpopup" $pmpopupnotchecked value="no"> no
	</normalfont></td>
</tr>

with this (yep, same as before):

<input type="hidden" name="pmpopup" value="yes">

That way, all new registrations will have it on by default, and on't be able to change it. Now, if you want to change it so that, after you've done this, ALL users have it set to on (and are therefore stuck with it that way, since you're removed the option to turn it off), you'll want to run this query on your forums DB:

UPDATE user SET pmpopup = 1

There ya go. Might wanna back this stuff up first, though, as I haven't tested it. It ought to work, though.