@babajagacoat I assume that by "backup" you really mean "upgrade", right? In this case, you can simply download the Joomla! 1.6.4 package from http://www.joomla.org/download.html, extract it locally and upload all extracted files to your site, overwriting the existing ones. If the error persists, one of your extensions is not compatible with Joomla! 1.6.4.
@cas Regarding the first issue, it's not possible to know beforehand which of the two methods works. Please note that the second and third line you posted use the same method (setting Options) which your host does not allow. I would argue that you do not need to enable that option if you have activated the front-end and back-end protection features of .htaccess Maker. These features will disallow access to any and every directory, except those that should be accessed over the web (those containing static media files, like CSS, JS and images). So even without the index disabling, your site is still protected. In fact, more protected than using just the index disable ;)
Regarding the mail issue, please note that .htaccess and mail live in different universes. One can not affect the other. The problem you have is that the mail options set in your site's Global Configuration seem to be wrong. This is where you should look to fix things. As I said, you can temporarily turn off the "System - Admin Tools Plugin" (so that Admin Tools' protection code does not get executed) and try using the Mass Mail feature. If it fails to deliver emails, go to your Global Configuration and fix the mail settings. If it does send out emails, please post back so that I can try to see why Admin Tools can't.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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