Explaining Permissions
There are 3 groups, self, group and public and three permissions you can give them: read, write and execute. Here's what they mean:
- Self: That's you. When you access your site with username and password, you're connected as the user.
- Group: That's you, too. And maybe others. If your site can be accessed with more than one username and password set, then those sets are also part of the group.
- Public: That's everybody else. You want to be very careful about the permissions you give them.
- Read: the ability to read a file.
- Write: the ability to modify a file.
- Execute: the ability to execute a file.
There's one final thing you need to know. Those permissions are sometimes given numbers:
- Read: 4
- Write: 2
- Execute: 1
They are also added up. So, if the "Self" has permissions of 7, that means they can Read, Write and Execute. If "Public" has permissions of 4, they can only Read.
Explaining How Permissions Affect Joomla
Go to your administrator control panel and then Help >> System Info >> Directory Permissions. You'll see a list of all the folders on your site and whether you have permission to access them. On the screen above, I can't access the /images/ folder or /images/banners/ or /images/stories/. If I want to upload images I'll need to change the red "Unwritable" to green "Writable". Here's how to do it:
Login to Your FTP or Hosting Account
In this example I'm going to use CPanel as it's very common, but really you just need a way to access your files. Inside Cpanel I'm going to click on "File Manager" which will allow me to access your files. However you get there, you should end up seeing a screen like the one below:
Viewing Your Files
We know we want to change permissions on the /images/ folder so fortunately we can see it in this list.
Choose to Modify Permissions
Check the box next to /images/ and then click "Change Permissions".
Change Permissions
You may well see a screen like this. You'll hopefully remember many of the permission settings from the first part of this tutorial. The one thing to avoid is 777 because that means anyone can do anything to your folders! The lower the numbers, the safer your site will be. A good setting to try here will be 755 but you may need to experiment because all servers are setup differently. Once you've made a change and clicked "Change Permission", go back to Administrator >> Help >> System Info >> Directory Permissions to see if the red "Unwritable" has changed to the green "Writable".
