How to Change Roundcube Skins
Roundcube is a Web-based email interface that allows users to log in and access their email system. Users can check their email, send messages and keep an address book. They also have access to some personal settings but can't change the interface skin; only the administrator has access to the Roundcube skins. If you want to change the skin, you'll need to log in to the Roundcube directory on your Web server and edit the "main.inc.php" file.
Launch your FTP client. Type your FTP address, username and password into the displayed text fields, then click "Connect."
Open the "Roundcube" folder in the server pane.
Open the "Skins" folder in the server pane.
Click-and-drag the skin subfolder of your choice from the local pane to the server pane to upload the Roundcube skin.
Click the "Up" or "Back" arrow to go back to the main Roundcube directory in the server pane.
Open the "config" directory.
Drag the "main.inc.php" file from the server pane to the local pane.
Right-click the "main.inc.php" file, then click "Open With." Click to select "Notepad" from the applications list, then click "OK."
Locate the "$rcmail_config['skin'] = 'default';" line of code, where "default" is the current skin directory. Replace the "default" text with the name of the skin directory that you uploaded to the "Skins" directory in Step 4. For example, if the skin was named "custom_skin," change the line of code to read "$rcmail_config['skin'] = 'custom_skin';"
Click the "File" menu, then click "Save."
Drag the "main.inc.php" file from the local pane to the server pane.
Click "OK" when prompted to overwrite the existing file.