Hi,
Does the problem occur in other applications? If not, then it's specific to the email application or, if web-based, the site or plugin that it uses. This would mean there's nothing wrong with your keyboard or the driver software, the interference is coming from the email process.
Best of Luck,
Rick Rogers, aka "Nutcase" - Microsoft MVP
http://mvp.support.microsoft.com
Windows help - www.rickrogers.org