I am having a similar problem and have searched all over the forums and tutorials/FAQ for a resolution. Here is what happened to me. I had my website and shopping site operational and running, then had to switch hosts because of extensive downtime. I had backups of most of my php and html files that I had changed, but not the database. So I installed Zen-Cart 1.3.7 on my new host (still the same locations, shop.gouldcomputing.us) and then started uploading my changed files one by one, making sure each one was fine as I went along. I never got any PHP errors, but I noticed later that my title bar is showing "META_TAG_TITLE", no matter where I go on the shopping site (I have not had a chance to add a product back into this, but on any of the other pages it still shows just the "META_TAG_TITLE"). My meta_tags.php file in /english and english/classic are fine and define TITLE as "GouldComputing" and also SITE_TAGLINE, etc. I notice when I view page source on my main page or any other page that it shows the following:
------------------------------------------<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" dir="ltr" lang="en">
<head>
<title>META_TAG_TITLE</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<meta name="keywords" content="META_TAG_KEYWORDS" />
<meta name="description" content="META_TAG_DESCRIPTION" />
<meta http-equiv="imagetoolbar" content="no" />
<meta name="author" content="The Zen Cart™ Team and others" />
<meta name="generator" content="shopping cart program by Zen Cart™, <http://www.zen-cart.com> eCommerce" />
<base href="http://shop.gouldcomputing.us/" />
<link rel="stylesheet" type="text/css" href="includes/templates/classic/css/stylesheet.css" />
<link rel="stylesheet" type="text/css" href="includes/templates/classic/css/stylesheet_css_buttons.css" />
<link rel="stylesheet" type="text/css" media="print" href="includes/templates/classic/css/print_stylesheet.css" />
</head>
----------------------------
I investigated the html_header.php in template_default/common
and from that it is picking up the CHARSET and HTML_PARAMS settings fine, but they are in english.php, not in the /english/meta_tags.php file.
I cannot remember if my old host had 1.3.7 installed or 1.3.6 - could this be the key?
Can anyone help with this problem? Nothing seems to work from all the other threads.
If anyone needs any more info, please let me know. Thanks!