IPSec is blocking network traffic

I have a windows 2003 Enterprise Edition x32 that after restarting stops responding on the network.

It is a domain controller that is also running Exchange 2003 Standard and one Virtual server instance.

The exact error message is "The ipsec driver has entered a Block mode.  IPSec will discard all inbound and outbound TCP/IP network traffic that is not permitted by boot-time IPSec Policy exemption."

One of the suggestions is to stop the IPSec services.  However I have a SSL certificate installed.

In addition to the ipsec error message there are 3 others that appear during the restart process all relating to the KDC service.

To fix the problem I simply do another restart and the server starts responding again and the error message goes away.

What on earth could be causing this?  Any suggestions would be appriciated.
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Krzysztof PytkoConnect With a Mentor Senior Active Directory EngineerCommented:
From eventid.net extract

"As per Microsoft: "This problem occurs because the DNS Server service is listening on the UDP port that is required by another service. This problem occurs when the MaxUserPort registry entry is present. This registry entry is located in the following subkey in the registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\". See M956189 for default values for MaxUserPort. "

Read those entries, maybe they will help you

Tony MassaCommented:
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