User Account changed

The Logon and Logoff options windows have suddenly changed from the "Welcome Screen" to the "Classic Logon Prompt". The "User Account - Select Logon and Logoff Options" window is gray i.e. it is not possible to select one of the options . Clicking on "Control Panel" -> "User Accounts" -> User accounts icon -> "Change the way users log on or off" a windows pops up with the following: "Client Services for NetWare has disabled the Welcome Screen and the Fast User Switching. To restore these features, you must uninstall Client Services for NetWare". Please , where can I find "Client Services for NetWare"? and How to modify it? Thanks

I solved the issue

I went to the "Local Area Connection Properties" and uninstall the "Client Services for NetWare" I found there checked.
The PC rebooted, Client Services for NetWare didn't reapeared on the list in the Local Area connection Properties window, but the issue remain unchanged.

I came back to the "Control Panel" -> "User Accounts" -> "Change the way Users log on or off" and I got the User Account - Select Logon and Logoff Options window with the options available.
I checked both options -> this solved the issue.

Thanks to everyone who tried to assist