If you are getting this error either in PowerShell or with the User Interface :
New-SpManagedAccount : The given key was not present in the dictionary
In order to fix this problem, you have to go in the Active Directory and give the “Authenticated Users” Read Permissions on the account (See image, it will be a lot more clear)
If you don’t see the “Security” Tab, make sure you have “Advanced Features” Available on your Active Directory. ([View]> Advanced Features)
Say thanks if this post helped :).
