Cannot login to control panel

[Magumo]

Good day,

On trying to login as admin on the Plesk control panel I get the error below. I have restarted the Plesk CP related services but still no joy.

Execute C:\Program Files\SWsoft\Plesk\admin\bin\vzutil.exe failed:
---------------------- Debug Info -------------------------------
0: plib\visibility.php:68
is_virtuozzo()
1: plib\visibility.php:68
getVisibilitySets(boolean true)
2: plib\visibility.php:516
isControlSetVisible(string 'promo_virtuozzo')
3: plib\ui\promotion.virtuozzo.php:92
plesk__promotion__virtuozzo->validateItem(object of type UserAdmin)
4: plib\UIPointer.php:978
UIPointer->validate()
5: plib\leftmenu.php:117
getNavigation()
6: htdocs\left.php3:8

Please help.