How to free up spaces on server mailboxes

delete a few large message rather than delete a lot of small mails

Clean up Junk and Trash

First, login to webmail (see How to open WebMail on computer)

Select the Junk mailbox, click the mailbox menu on top, select Empty

Do it again for the Trash mailbox

Clean up Inbox and Sent

Select Inbox

Click Options on top

Sort by Size, Decending

While holding the Shift or Ctrl, select some biggest messages you want to delete

click the Delete button

Do the same for Sent folder

After deleted messages, empty the Trash folder

After few minutes (not immediately), notice the free space changed

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