Is there a way to get the log of all the Approval emails sent from Salesforce. I tried to get the log of all the emails sent out by requesting for email log, but for some reason feel like the data is missing. Is there a easy way to monitor all the approval hierarchy emails sent from SF to a specific/ all the users.

In short : Is there a archieve where I could go and see if the email notification was sent out for a specific user (I know this is a standard functionality, but the user complaints he never got an email :()