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I have been working on this server for the entire semester and have not changed any configuration options - the directories/files I created a couple weeks ago are still accessible, however any new directories, even exact duplicate of old working directories don't let me access them - get error "Directory index forbidden by Options directive". What is causing this?
Looks like someone disabled directory listing in Apache. If you are allowed to override it with .htaccess just place an .htaccess file in your root web directory with this information:
Options +Indexes
For me this was an issue with not simply having an index.html or index.php (depending on what is in the .htaccess file) file in a folder and trying to pull it's contents. Then again I was using php to read contents, not by command line like I assume you are. If you still have not found a solution try creating an index.(php,html) in the directory that you can't pull contents from.
For me what helped was, walking thru the explanations in the httpd.conf file and making sure I am compliant. The below comment helped:
# The path to the end user account 'public_html' directory must be
# accessible to the webserver userid. This usually means that ~userid
# must have permissions of 711, ~userid/public_html must have permissions
# of 755, and documents contained therein must be world-readable.
# Otherwise, the client will only receive a "403 Forbidden" message.
I was trying to move the document root and I hadn't set up the right perms..
For me worked in Wordpress. Error was Forbidden access wp-admin. I created .htaccess with Options +Indexes content.
Thank you.
来源：https://stackoverflow.com/questions/10365520/error-directory-index-forbidden-by-options-directive