I'm using 128.5esr (64-bit) in Mac. There was a email in inbox ; I can mark it as read-under but cannot delete, move; I tried many times delete or move but nothing happened. After several restart that zombie email left but also I saw many empty folders which must have hundred emails in it...

my last backup belongs to months ago, so I lost all important emails. How to recover it I do not know. Any advice ?