Hi Theblip
I had a strange thing similar last week where an email 'disappeared'. After alot of searching I found that it was stuck in the 'out' but had not been sent. I didn't know about the out box, I always look in the sent folder. Also it may have been mis detected as spam? Just an idea.
Some of these answers are untrue. In MS Outlook the sender can recall an email without the receiver knowing as long as they haven't opened it. They will not get a message saying it's been recalled it will just disappear. It doesn't work if the receiver has opened it though. I know I'm correct as I use this feature quite often at work.
Yes you either get a message recall success or failure (as the sender). I have just done a practice with my husband as we're both currently logged into our work's system. I sent him an email. He saw it in his inbox but didn't open it as instructed. I then recalled it. I got a message of success and he got nothing except my mail had disappeared from his inbox, so he could have been none the wiser :-)
Sorry, you cannot delete an email that you have sent. Gmail does not have a cancel option; however, it has just an Undo Send option, which works only for a minute. You can’t do that without access to that inbox.