Reasons for blocking Webmail Access in the Workplace

1. Unwanted files and viruses *will* bypass your corporate email content filter / virus scanner.
   You will solely be relying on desktop scanners as our last line of defence.
    
2. Decrease in productivity, increase in chit-chat, increase in browse/surfing times.
   Which has already been proven in the past.
    
3. Unable to reliably track true email usage.
   Staff may send 2 business emails via Outlook, but use yahoo to send 50 personal emails, and we wouldn't know that.
    
4. Unable to any longer spot email abuse.
   See above. We would now have to go by surfing statistics.
    
5. Unable to archive email traffic between internal and external users.
   Because emails are no longer going through Exchange, and now look like standard web traffic which may bite us in a lawsuit, or in an internal situation where directors may demand to see all emails going between one
   specific employee and their contacts. We would not be able to prove certain emails were sent/received.
    
6. Greater chance of users clicking on cross-site scripting vulnerabilities, internet explorer vulnerabilities/exploits, and phishing scams.
   All of which are not being content filtered before arriving at people desktops.
    
7. Increased workload on IT staff.
   To keep machines disinfected from Spyware, unwanted files that the desktop virus scanners would not be able to pick up, and programs that people may have been able to install or copy over to their computer from a yahoo email.
    
8. Great possibility of business intelligence / Information leaks.
   Emails can be sent without anyone's knowledge which could damage our business or reputation. Emails are no longer captured, and so any impropriety (attaching any important files or leaking information etc.) cannot be proven.
    
9. Greater possibility of adult/porn content leaking through from webmail services,
   Since most email porn is spam generated, the risk of Hostile Workplace complaints will be increased because porn may pop up more frequently on people's desktops as reliable spam filtering is virtually non-existent on the webmail services. All web content, including potential adult content would also be downloaded onto local PCs.
    
10. Increased threat to the health of our internal network.
    Extremely new viruses/trojans that don't have virus definitions created for them yet have a higher chance of infecting PCs and servers on our network. Typically brand new viruses are caught by our corporate email content filter / virus scanner even if we don't have new definitions, however, if we're relying on a desktop virus scanner without the latest definitions, there is a great
    potential for considerable damage that would be done to our network, which may cost us major downtime and a damaged reputation.