At some point, hopefully sooner rather than later, I would imagine that every Joomla developer or probably more accurately, Joomla website maintainer will have to deal with a Joomla 1.5 to Joomla 2.5+ upgrade.

If you still have Joomla 1.5 sites and are wondering what I am going on about, then you need to read Fighting Website Hacks.

90% of the Joomla 1.5 migrations that I am involved with, rely on the use of the JUpgrade component released by redCOMPONENT. This tool really is invaluable for converting a large amount of content from an old Joomla install into Joomla 2.5.

However, as most developers might know, not everything goes as planned and works according to what is expected the first time around. There have been a couple of smaller non-obstructive issues that I have seen crop up during a migration, although there was one problem in particular which I hadn't heard of or were even familiar with.

This issue directly affects the entire website regardless of the page, where all article content failed to display without causing any system errors.

At first, the usual diagnosis follows by looking to make sure correct permissions are set both at an article level, but also as far as the Viewing Access Level permissions. When the permissions didn't seem to be out of place, I ventured into the template which was also brought along for the migration. The template also didn't produce any noticeable differences between the converted template and a stock template that comes with Joomla 2.5.

So naturally, I turned to Google as the faithful helper. As it happened, the issue was not that uncommon and I soon stumbled onto a very nice Joomla forum post. 

http://forum.joomla.org/viewtopic.php?f=615&t=600793

I finally figured it out!

I copied a 1.5 template and edited it for 1.6 but I still had the /html/com_content/... files of the OLD template. Once I deleted those the content showed.

Thanks Webdongle for your help and patience!!

~ LikeStuff

When I read this post, I was a little unsure about it at first however the number of people thanking LikeStuff for the solution was encouraging so I decided that I would give it a go.

Rather than fully deleting the com_content directory in the html override, I decided that a rename would be enough to get the desired changes to work.

Sure enough, no sooner did I rename the com_content directory did the article content start showing again.

So if you have issues with your article content not showing, make sure to check your html overrides inside your assigned template located in:

<joomla>/templates/<template>/html/com_content/