DAG Backup job cannot run. Please verify that all DAG members are upgraded

Hi ​@Jeton Aziri please try check readiness on DAG client to confirm if there are any issue members servers it is trying to connect

Hi, during discovery it shows the two exchange servers, but one of them is greyed out and im unable to select it. I selected only the second one, and backup completed successfully.

Any idea why the other is not available? Theres no issue with DAG, i installed/reinstalled the agent on that server again but its issue still persists.

hi ​@Jeton Aziri 
please check both nodes exchange package + host name of members nodes set to FQDN 
reference: https://kb.commvault.com/article/54027
issue we have seen due to multiple reasons like duplicate client entry as well where merge is required
https://kb.commvault.com/article/63652

please review if still a issue persists, please raise a support case we can identify and if needed resetdag scripts can be ran.