EC2 Permission Denied / Auth Failure Diagnostic Troubleshooter (Part 1)

Use the interactive troubleshooter below to identify your EC2 permission denied or auth failure symptom, review the raw evidence, understand the root cause, and apply the recommended fix.

🚨 Step 1: What specific error symptom are you experiencing?

Please click the most accurate description:

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Quick Reference Table

#	Scenario	Key Error Signal	Root Cause	The Fix
1	permission denied — No more authentication methods to try	debug1: No more authentication methods to try. / Permission denied (publickey).	The SSH client attempted to authenticate using a private key that is not recognized by the server.	Ensure the correct .pem file is used, or convert it to .ppk for PuTTY, and specify the correct AMI username.
2	permission denied — Permissions 0777 too open	Permissions 0777 for '.ssh/my_private_key.pem' are too open. / bad permissions: ignore key: .ssh/my_private_key.pem	The SSH private key file is unprotected and has overly permissive read/write access, causing the SSH client to proactively ignore it for security reasons.	chmod 0400 .ssh/my_private_key.pem
3	permission denied — Authentication failed, permission denied	Authentication failed, permission denied	The user is attempting to connect via SSH using the wrong default username for the specific Linux distribution AMI, or an incorrect private key.	Connect using the appropriate default username (e.g., ec2-user, ubuntu, admin, centos) and ensure the .pem file corresponds to the instance's key pair.