I hv found a 100 percent fix for this problem here goes.first go into regedit and then into the following subfolders
Hkey current user
Software
Microsoft
Windows nt
Current version
Winlogon
Shell is missing so right click on right side and click
new string value
Right click on new string
Modify
Type explorer.exe
Like I hv restart pc
This is for windows 7 64bit
Would highly recommend backing up after this hope this helps.
Sorry if you can't understand am a noob and was excited when I finally found this fix as I been stuck on this black screen for a month. Also wrote this fix on display forum.