Interesting, based on your reply, you are using a Windows computer. This issue is not as common as you might think, and therefore used to not be the case, but I'm hearing of it more and more lately. Windows 7 and below users can call the Army Enterprise Service Desk at [login to see] and ask for support.
Windows 8 users will want to install ActivClient 7.0.2.25 via links on: http://militarycac.com/army.htm#7.0.2.x_DOWNLOAD, the update it to 7.0.2.308 via links on: http://militarycac.com/activclient7update.htm. Windows 7 and below will want to install ActivClient 6.2.0.50 via links on: http://militarycac.com/army.htm, then update to the current version via links on: http://militarycac.com/activclient62update.htm Plus, users will want to go through this guide: http://milcac.us/tweaks
I'm still sorry to hear you are having these issues. But, until DISA knows about them, they can't assume you are having problems. They "think" everyone is getting on just fine, becuase they can't tell when it doesn't work. The way to contact them is via AESD at [login to see]
Some of my battles have had that issue as well betting the "This page can't be displayed " message. I was surprised to find out that a lot of soldiers in my unit didn't know that you don't have to go through AKO to get your Enterprise.
I suggest if it is not a certificate issue to make sure your using IE 10 in compatibility mode. Try to log into Enterprise, but use the web.mail.mil in the address bar instead of going through AKO.
Enterprise usually prompts me to select another address web.mail-st01.mil or something similar I enter in my pin, then I bookmark that address.
If you get the "This page cannot be displayed" again try clearing you cookies, closing completely out of your browser and try web.mail.mil again.
Technical Information (for support personnel)
Error Code: 500 Internal Server Error. The server denied
the specified Uniform Resource Locator (URL). Contact the server administrator.
(12202)

CAC
Supply
