Access Denied:
You don’t have permission to access {website name}  on this server.  Reference # {long string of text}

If you’re getting this message on certain sites you’re probably really confused. I had the same issue and here is what I determined.

Symptoms:

• When visiting a website, you get a pretty stark/plain error message saying your access to the site was denied and a cryptic error message
• It occurs on sites like cms.gov, healthcare.gov, usps.com, costco.com, godaddy.com

Why:

• What all these sites have in common is that they leverage the Akamai CDN. A CDN is a service that sites use to accelerate their content delivery and offload the traffic so that their sites can scale better
• Akamai provides an article titled Why is Akamai blocking me, but it’s basically useless.  They claim that they have no control, but it’s clearly their service which is providing a common “blocking” service to all their clients.

The Fix:

For me, I had a custom script running that would screen scrape certain websites every 5 minutes checking to see if an item was available to purchase.  The script was very non intrusive and I was cautious not to have something running that could be considered as malicious.  Unfortunately, somehow Akamai was able to detect this script was running on one of my home computers and subsequently banned my IP address.  The solution was to stop the script from running and then request my router to renew my DHCP lease with ISP (Optimum Cablevision) and get a new IP address.  Once I had a new IP address, there were no issues accessing the sites.  If your router is not allowing you to renew your IP address and if you are using DD-WRT, you need to enable Mac Address Clone to change your routers MAC address.  When your ISP sees you have a new MAC address it will assign a new IP.

Other items to look for is to ensure you have no malware running on any of your home computers or running an outbound email server.

Good luck!