From: Steve Gould on
I posted the following long ago.

The fix was suggested by "MC" from another web board. I tried it and it
fixed my issue. I knew what they fix needed to be (learned the hard way from
a similar issue in Exchange), I just didn't have another server to copy the
correct registry files from. Here is MC's reply to my posts:

As soon as I rebooted a Windows 2003 server after SP1 install I started
getting this error message:

Event Type: Information
Event Source: IAS
Event Category: None
Event ID: 5050
Date: 4/22/2005
Time: 5:00:44 PM
User: N/A
Computer: (Server Name)
The description for Event ID ( 5050 ) in Source ( IAS ) cannot be found. The
local computer may not have the necessary registry information or message
DLL files to display messages from a remote computer. You may be able to use
the /AUXSOURCE= flag to retrieve this description; see Help and Support for
details. The following information is part of the event: (DC
Name).(domain).org, (NetBIOSDomain).

The error repeats every 30 minutes or so. I could find nothing in TechNet
that gave me a clue where to look. All that was listed as DNS and it looks

Anyone have any suggestions?

On a Windows 2003 server acting as an RRAS server with IAS, the IAS event
entries appear in the System log, but I noticed on our ISA 2004 server that
the IAS events were appearing in the Application log instead.

I found that if I copied the event message file settings from a non-ISA
server running IAS onto our ISA server, but changed the location so that it
allowed Application log entries to be interpreted I could read the event log
entries without any problems.

In short, I created a new regkey called:


Then adding the same values from the non-ISA IAS server:

EventMessageFile (REG_EXPAND_SZ) =
ParameterMessageFile (REG_EXPAND_SZ) = %SystemRoot%\System32\iassvcs.dll
TypesSupported (REG_DWORD) = 0x0000001f (31)