One of my Windows XP Professional clients started recording the following in the System event log:
Event Log Error 5719
Description: No Windows NT or Windows 2000 Domain Controller is available for domain Domain. The following error occurred:
There are currently no logon servers available to service the logon request.
However, the client was able to log onto the domain and access resources on the domain controllers.
I had made no changes to this client, and it had been running flawlessly.
I tried all the tips on this site, including delaying the start of the NETLOGON service.
I finally replaced the supported network adapter, on the assumption that it may be in the early stages of hardware failure, and this resolved the problem.