I ran into the following error today while attempting to create a Lambda function using the CLI:
The first thing to check is that your aws config is setup correctly. For me this is under c:\users\chris-pc\.aws\.
If that looks fine, double check that the associated user has the correct rights by viewing the IAM page in the server console: https://console.aws.amazon.com/iam/home
Finally, ensure that the user has programmatic access and that the keys match those in your config.