AWS documentation for: EC2 "Launch more like this"
Launch more like this option is not available anymore.
Launch more like this will launch another instance (or more) with the same settings as the selected instance (EBS, AMI, Security Groups, etc).
If you would like to launch an instance with the exact same data (basically a clone of the selected EC2 instance) you should create an AMI (in case of EBS backed instances, you can create an AMI by right clicking the instance in the Web Console) and launch instances with that AMI.
You can also create AMIs from previous EBS snapshots of your EBS device (also available from the EC2 Web Console).
Even though this question has an accepted answer I am pasting the details straight from the AWS doc. The following configuration details are copied from the selected instance into the launch wizard:
AMI ID
Instance type
Availability Zone, or the VPC and subnet in which the selected instance is located
Public IPv4 address. If the selected instance currently has a public IPv4 address, the new instance receives a public IPv4 address - regardless of the selected instance's default public IPv4 address setting. For more information about public IPv4 addresses, see Public IPv4 addresses and external DNS hostnames.
Placement group, if applicable
IAM role associated with the instance, if applicable
Shutdown behavior setting (stop or terminate)
Termination protection setting (true or false)
CloudWatch monitoring (enabled or disabled)
Amazon EBS-optimization setting (true or false)
Tenancy setting, if launching into a VPC (shared or dedicated)
Kernel ID and RAM disk ID, if applicable
User data, if specified
Tags associated with the instance, if applicable
Security groups associated with the instance
The following configuration details are not copied from your selected instance; instead, the wizard applies their default settings or behavior:
Number of network interfaces: The default is one network interface, which is the primary network interface (eth0).
Storage: The default storage configuration is determined by the AMI and the instance type
NOTE
The Launch More Like This wizard option does not clone your selected instance; it only replicates some configuration details. To create a copy of your instance, first create an AMI from it, then launch more instances from the AMI.