创建带AdministratorAccess权限的IAM用户后遇认证错误求助

Hey there, let's work through this annoying login issue you're hitting with your new IAM users. It's weird that existing users work fine but new ones are failing—let's break down the most likely fixes step by step:

• Double-check your IAM user login URL
  This is the #1 mistake people make. Root user login URLs won't work for IAM users. You need to use the account-specific IAM login page:
  https://<your-aws-account-id-or-alias>.signin.aws.amazon.com/console/
  If you're using the generic AWS sign-in page, make sure you select "IAM user" and enter your account ID/alias correctly before inputting the username and password.

• Verify the new user's password status
  Head to the IAM console, find your new user, and go to the Security credentials tab. Check if:

  • A console password is actually set (sometimes you might forget to generate one during user creation)
  • The password status is marked as Enabled (it could have been accidentally disabled)
    Try resetting the password, check the box for Require password reset on next sign-in, and use the new password to log in.

• Confirm username and password accuracy
  IAM usernames are case-sensitive—if you created a user named EC2Admin, logging in with ec2admin will fail. Also, double-check for typos in auto-generated passwords (they can have tricky special characters). Try pasting the password directly if you copied it, or manually type it slowly to avoid mistakes.

• Rule out browser caching issues
  Sometimes old login cookies or cached credentials can cause conflicts. Try logging in using a private/incognito window, or clear your browser's cache and cookies before attempting again.

• Check for account-level restrictions
  Even with full admin permissions, there might be global policies blocking login:

  • Service Control Policies (SCPs): If your account is part of an AWS Organization, make sure no SCP is denying iam:Login or console access for new users.
  • Account-wide IAM policies: Look for any managed or inline policies attached to the account (not just the user) that might include a Deny effect on console login actions.
  • MFA requirements: If your account has a policy forcing MFA for console access, new users won't be able to log in until they set up an MFA device. Check if existing users have MFA enabled, while new ones don't.

• Test with a minimal, fresh user
  Create a brand new IAM user with just the AdministratorAccess managed policy (no copied permissions or extra inline policies) and a new password. Try logging in immediately—this can help rule out issues with permission copying or corrupted user configurations.

Since you already tried a full-access inline policy and copying existing user permissions, the problem is almost certainly related to login configuration rather than permissions themselves. Start with the first two steps—they fix 90% of these cases!

内容的提问来源于stack exchange，提问作者thuy