You might not have permission to use this network resource error.

do the following to solve this error

 

1. Click Start, click Run, type regedit in the Open box, and then click OK.
2. Locate and then double-click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l\Lsa
3. In the right pane, double-click restrictanonymous.
4. Make sure that the value in the Value data box is set to 0, and then click OK.
5. Close Registry Editor.
6. Restart the computer.

How can I enable / disable the Ctrl Alt Del from logon screen ?

Do the following ...

Start the registry editor (regedit.exe)

Move to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows
NT\CurrentVersion\Winlogon

Double click on DisableCAD (create of type REG_DWORD if it does not exist)

Set to 1 if you don't want to have to press Ctrl-Alt-Del, and set to 0 if you do. Click OK

Close the registry editor

Reboot the machine