hello name is tony did a dell pc restore but cant see waht to do next?

had some very bad virus had the guys at geekpolice get rid of it but before they were done left and my gpa restarted computer now it just says
THE LOGON USER INTERFACE DLL FAILED TO LOAD

CONTACT YOUR SYSTEM ADMINISTRATOR TO REPLACE THE DLL OR RESTORE THE DLL OR RESTORE THE ORIGINAL DLL.

did a dell pc restore from computer but screen has been out for awhile now can only see very little its dark but my other lcd i had hooked up to it is not recieving anything might be the driver after restore but see very little can anyone help with step by step instructions cant really see anthing on there plz?

Moved to hardware//

Hello, please do the following:

Restart your computer, once it starts to restart, press the F8 key continuously. If done properly you will be in the windows advanced options menu, from their use the arrow keys to highlight "Last Known Good Configuration" and press enter. Does it work now?