Checking Mailbox Usage
Log into hosting.mandraled.com, navigate to Email Accounts, and view the usage display next to your mailbox.
Solutions
Add Storage Capacity: You can increase the size of your mailbox in 10GB increments by ordering a Mailbox Quota Addon from the Mailbox Usage page.
Clean Trash Folder: Deleted emails occupy server space until permanently removed. Most mail clients offer options like "Empty Trash" or "Erase Deleted Items" to free this space.
Remove Sent Messages: Deleting your sent items will not mean they are deleted from the recipients' mailbox, just the mailbox they were sent from. Users can selectively delete or bulk-clear sent items.
The guide emphasises that permanently deleting items from trash means they cannot be recovered.