To subscribe or unsubscribe to folders in the SquirrelMail interface, perform the following steps:
Step 1: Navigate to the top of the SquirrelMail interface and click Folders. The Folders interface will appear.
Step 2: Locate the list of available folders in the Unsubscribe/Subscribe section.
Step 3: To subscribe to folders, select the names of the folders that you wish to view from the right menu and click Subscribe.
Step 4: To unsubscribe from folders, select the checkboxes that correspond to the names of the folders that you no longer wish to view from the left menu and click Unsubscribe.
Step 5: Click Check Mail in the top left corner of the SquirrelMail interface to refresh the list of folders.