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Event Viewer problem: Event ID: 5050 IAS - Local computer does not have the necassary DLL files to display message

Encams asked
Medium Priority
Last Modified: 2012-06-27
On my exchange server i've had this recent event log entry come up in my Application event viewer:

Event Type:      Information
Event Source:      IAS
Event Category:      None
Event ID:      5050
Date:            22/03/2006
Time:            15:31:31
User:            N/A
Computer:      EXCHANGE


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: EXCHANGE.DOMAIN.co.uk, DOMAIN.

And this entry appears every 30mins or so.

I have tried to open the log on a couple of other computers using the AUXSOURCE flag, but i still get the same message and nothing different.

Any idea what is causing this message and how i would go about correcting it?

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I'm still getting these errors - about 20 a day!

Can no-one point me in any direction to fix it?!

I get them all the time, too, on several SBS2003 SP1 Servers.  Wondering if it's related to Exchange ActiveSync authentication?


No idea,

I've got 4 Win2003SP1 servers in the domain and only the Exchange server is producing this error.
It happenend after i finished all the outstanding Windows 2003 patches and fixes.

vsg375: No points involved yet, and I don't want any, but I would ask you to keep the question open for a while longer, please.

Encams: I found just a couple of posts on other forums about this--as you probably have--but no answers.  One person says the message logs on a 2003sp1 server every time an RDP connection to it is attempted and hangs (then second attempt succeeds; stranger still).  Another person thought it might be related to having previously had a 2003sp1 server configured as a RADIUS server, but he never did get to the bottom of it.  As another user in that thread finally suggested, it must just be a bug (and a low priority for Microsoft), and it doesn't actually seem to reflect a problem (it is, after all, an "information" event).

So, I'm going to move on with life....

I have no problem with keepink the Q open for a while, as long as you are willing to work on it ;o)

EE Cleanup Volunteer


It is a bit rubbish isn't it.

The server is just and Exchange server and has never used Radius, i've read a lot of posts elsewhere with similar people reporting the same problem, but no solutions (so far!) What really annoys me is the fact Microsoft haven't documented this error in anyway.

PAQed with points refunded (500)

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The best I could figure out was that there are some messaging dll's missing and adding them might fis the issue. I am not sure what they are though and a reinstall over the old version might add them.

Create a new reg key:


Then add these values:

EventMessageFile (string Value) = %SystemRoot%\System32\iassvcs.dll;%SystemRoot%\System32\mprmsg.dll;%SystemRoot%\System32\ws03res.dll

ParameterMessageFile (string Value) = %SystemRoot%\System32\iassvcs.dll

TypesSupported (REG_DWORD) = 31(decimal)

As soon as I did this the Event Log was able to read the event - "A LDAP connection with domain controller was established"
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