What does the downwards arrow symbol on a User mean in Active Directory
I have created a user account called "MyUser" via Powershell, and the icon graphic in active directory different to that of the user test that I create via the UI.
The scripted one has a circle icon with a downwards facing arrow: 
The UI generated user does not has an icon that does not have the downwards facing arrow.
Solution 1:
It means that the user object is disabled. You can right click the object and choose the "enable" option to enable it.