When I was configuring a new installation of SharePoint Server 2010 the other day, I hit a snag when creating a Managed Service Account while creating a new Web Application.  My existing Application Pool account wasn’t listed and I couldn’t choose the “Configurable” option to manually type it in.  I attempted to make the existing application pool AD account a managed account, but got the error:

“The given key was not in the dictionary”

To correct this error, you need to go into Active Directory and make a security change:

  1. Open up Active Directory Users and Computers
  2. Click View, and click the option Advanced features
  3. Right-click the account you want to make managed and choose Properties
  4. Click the Securities tab
  5. Under the Group or user names: box, highlight Authenticated Users
  6. Under the Permissions for Authenticated Users box, click Allow for the Read permission.  Click Ok.
  7. You should now be able to create the Managed Account without error.

Active Directory Managed Accounts Fix