DR4100 connection failed with error "This device has not been discovered".

Hi Team

I need a solution.

I amd using Symantec backupexec 2014 sp2 on windows server 2014. I am using DR4100 dedupe device with it. Firstly it was working fine but then it unable to connect with DR4100 container and shows the following error.

also i connect manually through DR4100 but it gaves this error.

I make another container on DR4100 and connect it with symantec and it is running normally.

further i restart the Dr4100 and Symantec services and server as well but issue is still same.

kindly help for this