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Error - Can not Sign into Communication Service ( Office Communicator 2005 - LCS 2005 Scenario )

manu4u asked
Medium Priority
Last Modified: 2013-11-29
I have setup Live Communication Server 2005 in our Windows 2003 AD Environment.
Installation was successful with out any problem.

From my Laptop, I tested the connectivity with LCS Resource Kit . And by suing LCSDiag.exe TOOL , Every settings is Ok .. I am using TCP currently , so the port is 5060. I am able to connect to LCS with my AD Username through this LCSDIAG utilty successfully,

But, when I used the Communicator Client 2005 , it returns the following error

"Can not sign into Communicator Service. You may have entered you sign-n name,username, or password incorrectly, or the authentication service may be incompatible with this version of the program. If your sign-in information is correct and the problem exists, contact your system administrator"

I am pretty much sure that my Login information is correct.

Any help would be much appreciated.

Watch Question

Hayes JupeIT Director

so are you using autodiscovery for server location or manual location? if you havent setup the DNS SRV records for autodiscovery, you must manually configure your communicator client (or use group policy)


I did set up DNS SRV and also I tried manual as well.
As I said, when I tried with RESOURCE KIT Tool , LCSDIAG.EXE , TEST is successful. I am able to Login with it.
But while using Client, The same error pops up.
I formatted and reinstalled the Whole thing again, but still the same error.

Hayes JupeIT Director

not sure what formatting and starting again is going to help with.
In your application event log some details will be logged as to why you cannot connect - could you please provide them ?
Dear Hayes,

I solved the issue... Anyway, thanks for your comments ..

You know what , this time I did not install COMMUNICATOR PATCH .

I think the patch was causing the problem.

Not the solution you were looking for? Getting a personalized solution is easy.

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Hi Manu,

How do you solve the issue.  I am getting the error .. Help me out.


M. Senthil Kumar.
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