How do I troubleshoot issues when I install or update SSM Agent on my Amazon EC2 Windows instance?

Yes, you can launch EC2 instances with predetermined private IP addresses using Amazon Virtual Private Cloud (VPC).

Here are some methods you can try to resolve the 'Permission denied (publickey)' or 'Authentication failed, permission denied' errors

1. Verify the User Name: Ensure that you’re using the correct user name for your AMI.
2. Check File Permissions: Verify that the file permissions within the operating system are correct and that the correct SSH public key is in the authorized_keys file.
3. Enter Key File Password: Enter the password for your key file or use ssh-agent to load the key automatically.
4. Check Instance’s Permissions: Check that the instance’s permissions are correct and the correct SSH public key is in the authorized_keys file.

If you copied your SSH keys from another source, you might encounter a permission denied error. This can happen if the file permissions on the SSH keys are too open. It’s simply not allowed to have 777 permissions on the public or private keys. You can set the following permissions on the ssh directory and its files:

.ssh directory: 700 (drwx------)

public keys: 644 (-rw-r--r--)

private keys: 600 (-rw-------)

authorized_keys: 600 (-rw-------)

known_hosts: 600 (-rw-------)

config: 600 (-rw-------)

You can change these permissions using chmod command.

If these methods don’t work, you might need to check your SSH configuration file or restart your SSH service.

You may encounter difficulties updating Windows on your Amazon EC2 Windows instance due to potential connectivity issues preventing access to the Microsoft KMS server, leading to Windows activation errors. You can troubleshoot network and firewall configurations to resolve this problem.

The AWSSupport-TroubleshootRDP runbook enables the user to make changes in the common settings on the targeted instance which might impact Remote Desktop Protocol (RDP), for instance, the RDP port, NLA and Windows Firewall profiles. It is optional that the changes can be done offline by stopping and initiating the instance if the user specifically enables offline remediation. Then the runbook is able to read and provide the utility of the settings.

To access EC2 instance when RDP is not working:

• Troubleshoot the error message An internal error occurred.
• Troubleshoot with an instance screenshot.
• Confirm that you're using the correct IP address.
• Confirm that port 3389 isn't blocked.
• Verify that you are using the right firewall and network configuration.