Especially works for Vista Home Series
– Click start
– Type: regedit
– Press enter
– In the left, expand these folders: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\
– In the left, click on the folder named: Lsa
– In the right, double-click “LmCompatibilityLevel”
– Type the number 1 and press enter
– Restart your computer
PS: LmCompatibilityLevel default value is “3”.