Just a thought. You could have a computer security issue. Your gmail address could be being used as a dead drop by someone who has pinched your password. I recommend that you make sure your computer is fully up to date with security patches, anti-virus and spyware definition files, and that you run a deep scan to check for nasties: you can never be too safe, especially with the prevalence of keyloggers and trojans out there. If you've used a public terminal to check your email then you really should change your password from a secure computer. Apologies if I'm teaching granny to suck eggs but this looks quite suspicious and you could be vulnerable to further problems . As gmail doesn't actually delete anything it might be worth checking the archive for messages received that someone else has read and then deleted. HTH