When I open the replication tab for any path in CRX, it shows 500 internal server error. I have logged in as admin user and my AEM version is 6.5.6. Please advice.
Are you logged in as admin user? Usually this error comes up during Adobe outage/maintenance.
Can you try opening this:
Please check: https://status.adobe.com/
Also, contact AEM Customer support to get clarity.
A restart helped fix the issue.