IIS Configuration issues
Check the pre-requisites as per the help file:
Microsoft Internet Information Services (IIS) v7 or greater (IIS v7.0 and v7.5 will require the following hotfix to be applied - http://support.microsoft.com/kb/980368 KB980368)
IIS and ASP.NET Modules - setup instructions (see section 'Installing IIS and ASP.NET Modules') http://www.iis.net/learn/application-frameworks/scenario-build-an-aspnet-website-on-iis/configuring-step-1-install-iis-and-asp-net-modules
Windows Authentication role service to be able to use Windows Authentication on IIS - setup instructions http://www.iis.net/configreference/system.webserver/security/authentication/windowsauthentication
If the issue persists. It will be a problem with the password for the SDCService user.in the IIS site:
Open IIS Manager, and open the tree view for Application Pools. Find the SDC application tat is stopped, right click and select Advanced Settings…
Under Process Model. Click the ellipsis on the Identity line
Choose Custom account and set the correct user name and password for the SDCServiceUser account.
Start the IIS application and retry
Note the password for this user may need to be updated in Control Panel>User Accounts (for a local user) and in the login properties of the SDC services.