can you please post the screen shot?

hope you are using sylink replacer for SEP 12.X version?

You can also refer to:

How to change the sylink.xml file in Symantec Endpoint Protection (SEP) 12.1
http://www.symantec.com/business/support/index?page=content&id=TECH157585

What version of Windows?

Hello,

I would request you to check these Articles:

Cannot manually copy Sylink.xml into a Symantec Endpoint Protection 12.1 client. Access is Denied.

http://www.symantec.com/docs/TECH165321

How to change the sylink.xml file in Symantec Endpoint Protection (SEP) 12.1

http://www.symantec.com/docs/TECH157585

Hope that helps!!

Try with disabling tamper protection.

I think you are using 12sylink replacer.

Try to stop SEP service called Symantec Endpoint Protection then try to replace sylink.xml it should help.

BTW check your own permissions to file if everything is ok and you should have ability to replace the file and still can't do this try to stop SEP service then change it to disable and then restart computer (in my case it helps serveral times.)

You can use SEP user interface. Just open GUI of Symantec Endpoint Protection client and click HELP then chose Troubleshooting.

Next, in Communication Settings just import XML file (but check if your client is self managed or no)

How are you doing the sylink replacement - there are different methods to achiev that. Youmay want to choose one of the automatic ways like sylink drop or sylink replacer.