Symptoms
Assume that Microsoft Internet Explorer Enhanced Security Configuration (ESC) feature is enabled on Windows Server. In this situation, you cannot sign in to Microsoft Visual Studio 2013 Release Candidate (RC). Additionally, when you access http://app.vssps.visualstudio.com in Internet Explorer, you receive the following message:
Content within this application coming from the website listed below is being blocked by Internet Explorer Enhanced Security Configuration.
http://app.vssps.visualstudio.com
Cause
This issue occurs because that Enhanced Security Configuration feature blocks the online service URI that is needed by Visual Studio.
Note The restrictions that disable JavaScript or cookies also prevent Visual Studio from signing in correctly.
Workaround
To work around this issue, click Add to add the required URLs into the Windows Server exclusion list, restart Visual Studio, and then try to sign in again.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More Information
Check out the other known issues that you may experience after you install Microsoft Visual Studio 2013 RC.