Issue to cancel a mail too big in size

I am a Gmail user. I created a mail with some photos attached, and try to sent it, but the mail was too big and rejected by Gmail. I was thus getting regular rejection message from Gmail each time EM Client was retrying to send the mail. I tried to move the mail from the  “Waiting for Send” to the dustbin,. Mail desapeared from the box but I am now getting regular message from Gmail rejecting the move to the dustbin because because of a size too large.
Is there a way to completely remove this mail without bothering GMail.  

even the Trash folder is being synchronized with the server, so the best way to go about this is to click File>Work Offline to disconnect eM Client.
Then locate your message and delete it completely (even from Trash).
Restart eM Client and change back to online Mode by unchecking the Work Offline option again.


Seems to work. Thanks.