AWS made some big changes to improve security a few years ago.
This means that old accounts will not work with LaunchPal.
If you created your AWS account after 4 December 2013 your OK and can ignore the information on this page.
If you created your account on or before 4 December 2013, then please check the special AWS sub-account guide to show you the easiest & best way to get a new account.
In simple terms - before December 2013 - your account most likely will not support the more secure EC2-VPC, and will have used EC2-Classic.
VPC is a way of securing the network for your AWS instances.
LaunchPal is not compatible with EC2-Classic and requires EC2-VPC.
Here is the relevant information from Amazon - in their classic "Please read this 17 times" style.
If you created your AWS account after 2013-12-04, it supports only EC2-VPC
If you created your AWS account before 2013-03-18, it supports both EC2-Classic and EC2-VPC in regions that you've used before, and only EC2-VPC in regions that you haven't used.
If you created your AWS account between 2013-03-18 and 2013-12-04, it may support only EC2-VPC, or it may support both EC2-Classic and EC2-VPC in some of the regions that you've used.
If your AWS account supports both EC2-Classic and EC2-VPC and you want the benefits of using EC2-VPC with the simplicity of launching instances into EC2-Classic, you can either create a new AWS account or launch your instances into a region that you haven't used before.
Reading through AWS support documents about EC2-Classic, EC2-VPC and Default VPCs, it seems that with a lot of work it is possible to change an account.
But honestly the better option is to just create a new account, It's super easy now with AWS Organisations.
Changing your existing account is a bloody pain!
It involves terminating all non-VPC provisioned Elastic Load Balancers, Amazon RDS, Amazon ElastiCache, and Amazon Redshift resources in that region.
Here is the info from Amazon:
I really want a default VPC for my existing EC2 account. Is that possible?
Yes, however, we can only enable an existing account for a default VPC if you have no EC2-Classic resources for that account in that region. Additionally, you must terminate all non-VPC provisioned Elastic Load Balancers, Amazon RDS, Amazon ElastiCache, and Amazon Redshift resources in that region. After your account has been configured for a default VPC, all future resource launches, including instances launched via Auto Scaling, will be placed in your default VPC. To request your existing account be setup with a default VPC, contact AWS Support.