Lauching an instance

The error message "Invalid BASE64 encoding of user data" typically indicates that the user data used to launch the instance is not properly encoded in BASE64. User data is data that is passed to the instance at launch time, and it is often used to configure the instance or run scripts when the instance starts.

In this case, it is likely that the data you are trying to pass to the instance is not properly encoded in BASE64 format. You should check the user data you are using to launch the instance and make sure that it is properly encoded.

You can use an online tool to encode your data in Base64 or use an inbuilt command on your system. For example, on Linux, you can use the base64 command to encode data:

echo "your_data" | base64

or on windows, you can use the certutil command

certutil -encode input_file.txt encoded_file.txt

certutil -encode input_file.txt encoded_file.txt

You should also verify that the data you are passing to the instance is valid and does not contain any errors or syntax issues. Make sure that the script or user data is in the correct format and if it's a script then is properly formatted and has execute permissions.

Additionally, you can also check the user data section and the script you are trying to run on the instance in the EC2 console. This will help you verify if your script is in the correct format and if it has any errors.