Troubleshooting 403 Error accessing Admin panel

Question

When I attempt to log in to the admin panel of my site (Joomla 2.5), I get a 403 permission error. A number of sources report solutions (none of which have worked in my case, see below) and I am wondering how to troubleshoot this problem appropriately.

Some points

• the main website is functioning properly, and there is no evidence that the site has been hijacked
• I have successfully accessed the admin panel in the past with my current credentials
• My error log reports that client denied by server configuration
• As noted here the permissions of the administrator folder are set correctly
• There is no .htaccess file in the administrator directory. There is one in the main website directory with a Limit POST entry.
• Some instances of this problem appear to be resolved by contacting the host of the webserver. I'm currently in communication with my provider, and will delete this question if the problem is not Joomla-related.

(Do we need an administration tag?)

Answer 1

I recommend double-checking any rules you have loaded through your .htaccess/web.config file. I've seen people throw in custom rule-sets to manage the /administrator/ directory that don't quite cooperate with their hosts Apache/IIS configuration.

Of course, it maybe worth loading a fresh Joomla instance under a subdomain or another account under your control inside the same hosting environment to see if the problem persists.

From my experience, if it isn't any of the above(including the permissions/ownership issue that has already been cleared), it's usually hosting-related. And of course, from there we get into an entire paradigm of elements(type of host stack, modules loaded for stack elements(PHP, MySQL, Linux, etc)). But you would likely be getting more involved error messages.