A. By default an NT machine (since version 3.5, 3.1 only stored the last 1) caches the last 10 succesful logons, however this can be changed from anywhere between 0 and 50.

  1. Start the registry editor (regedit.exe)
  2. Move to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
  3. From the Edit menu select New - String Value.
  4. Enter a name of CachedLogonsCount and press enter
  5. Double click on the new value and set between 0 and 50. 0 means no logons will be cached, 50 will cache the last 50. Click OK
  6. Close the registry editor
  7. Reboot the machine

If someone attempts to logon and the domain controller is not available but their information is cached they will received the message

"A domain controller for your domain could not be contacted. You have been logged on using cached account information. Changes to your profile since you last logged on may not be available."

but still be logged on succesfully. If their information is not cached they will get the message

"The system cannot log you on now because the domain <domain name> is not available"

and not be logged on.