How to Change File Permissions Using Filezilla on Your FTP Site

By Lisa Sabin-Wilson from WordPress Web Design For Dummies

Every file and folder that exists on your web server has a set of attributions, or permissions, assigned that tells the web server three things about the folder or file. On a very simplistic level, these permissions include:

Read: Determines whether the file/folder is readable by the web server

Write: Determines whether the file/folder is writeable by the web server

Execute: Determines whether the file/folder is executable by the web server

Each set of permissions has a numerical code assigned it, identifying what type of permissions are assigned to that file or folder. There are a lot of them, so here are the most common ones that you run into and deal with when running a WordPress website:

644: Files with permissions set to 644 are readable by everyone and writeable only by the file/folder owner.

755: Files with permissions set to 755 are readable and executable by everyone, but only writeable by the file/folder owner.

777: Files with permissions set to 777 are readable, writeable, and executable by everyone. Don’t use this set of permissions, for security reasons, on your web server unless absolutely necessary.

You may run across a situation where you’re asked to edit and change the file permissions on a particular file on your web server. With WordPress sites, this usually happens when dealing with plugins or theme files. This practice is also referred to as CHMOD, or Change Mode. When someone says, “You need to CHMOD that file to 755,” you’ll know what to do.

Connect your FTP client to your web server.
Locate the file you want to CHMOD.

Files on your computer as well as files on the hosting account display.
In FileZilla, right-click the file on your web server and choose File Permissions to open the file attributes for the file.

The Change File Attributes dialog box open.
Type the correct number in the Numeric Value text field.

This is the number assigned to the permissions you want to give the file. Most often, you’re given directions by the plugin or theme developer on which permissions number to assign to the file or folder, and typically, it’s either 644 or 755.
Click OK.

The file saves with the new permissions assigned.