The given key was not present in the dictionary

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

SharePoint PowerShell New-SPManagedAccount error, The given key was not present in the dictionary (opens in a new tab)
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)

Active Directory user properties Security tab granting Authenticated Users the Read permission (opens in a new tab)

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 :).