where have my sent emails disappeared to?

My sent emails have disappeared. I have a sent folder in local folders but only 3 very old emails appear there. I also have a sent folder under Gmail heading  and the few same emails appear there.  I do not have a sent folder under “smart folders” although it was there initially. So where are all my “sent” emails? They are still in my gmail account. This happened before and I had to uninstall and reinstall. I am not prepared to keep doing this - very frustrating!  

Right-click on the GMail All Mail folder in eM Client, then choose Properties > Repair.

I do not have a Gmail " all mail folder " I have looked for “properties” and “repair” against any folder showing and the only repair button is under my gmail address. This says there is no information?

Is your GMail account setup as IMAP or POP3?

If you go to Menu > Tools > Accounts, clicking on the account should indicate how it is setup. So for IMAP it will look something like this: