File and Print Sharing Not Available

You like to share your disk or printer, but when attempting to install
it from the Network-applet, the button "File and Print Sharing" is missing:

Lets try to install it using the button "Add":

"File and printer Sharing for Microsoft Networks" can be selected from
the list of "Network Service", however when clicking on "OK" you get:

This gives us at least a hint: "Policies"
Using POLEDIT (Installation of POLEDIT), we check the Registry:

and look (= double-click) "Local Computer":

We found already the de-activation, it could have also be defined
as part of "Local User":

Taking off the Checkmark allows you again to activate "File and Printer Sharing".

However: You take the Checkmark off, but after the next reboot, the
checkmarks are again set.
Are you connecting to a Windows NT Domain server ?
Check in the Network Neighborhood for your server the share NETLOGON:

If there is any file-type "pol" (like: CONFIG.POL"), then your network administrator is imposing
a System Policy on you, please contact your network administrator to discuss the issue.