'Read More' not showing in posts

I know this subject is covered in the well known support article ‘Customizing the Read More’ and believe me, I’ve read it along with searching through similar ‘Read more text’ problems on the support forum.

My topic title indicates that I can’t get the ‘Read More’ to show in abbreviated posts.

“So what’s the idiot not done?” I hear you say.

Well, here’s the state of play:

I’ve been following the ‘Build your own WordPress theme’ tutorial done by Smallpotato and all the <?php the_content();?> PHP tags in all the template files read as <?php the_content();?>

all my current test postings were done without using the more quicktag and appear abbreviated with (a non-hyperlink) […]

I have edited some of the previous posts and inserted the more quicktag where I wanted the ‘Read More’ to appear in place of the […]

I edited the <?php the_content();?> in my index.php file to read:

<?php the_content(‘Read more…’);?>

However, no changes were made to the edited posts and the abbreviated posts still display […]

Are there other template files I need to edit and change to <?php the_content(‘Read more…’);?> where that tag appears?

Or is there other code I should be checking to make sure things are set up correctly to make use of the more quicktag?