The correct folder for gmail is named Sent Mail, and can be subscribed by right-clicking the account in the Folder Pane, Subscribe. Is that the one you deleted or unsubscribed?

I have a similar problem with an optusnet email account. The folders for 'Sent', 'Drafts', etc have disappeared. The only folder I can open is the Inbox. but it seems to have 304 items in it. yesterday I deleted items until there were less that 150.

I tried Right clicking on the email name and got to 'subscribe', but even with all the boxes ticked , only the Inbox is visible. Any suggestions please?