The C:\ProgramData\Amazon\EC2-Windows\Launch\Log\UserdataExecution.log Log-File

This file tracks the top-level execution of any tasks specified in a Windows Server EC2’s userData payload. This file should always exist. The primary reasons that it may not exist are:

• The EC2 was launched from an AMI that leverages the EC2Launch v2 method

• The EC2 was launched from an AMI that does not have the tooling to support parsing/executing a userData

Windows AMIs published through the Amazon/Microsoft partnership will always contain the tooling to support either the EC2Launch or EC2Launch v2 parsing/execution of userData payloads:

• Windows Server 2022 and higher AMIs use the EC2Launch v2 userData payload-handler

• Windows Server 2012, 2016 and 2019 AMIs use the EC2Launch userData payload-handler unless their AMI-names start with the string “EC2LaunchV2-”

To get a list of Windows AMIs that leverage the legacy EC2Launch userData payload-handler, use a (CLI) query similar to:

aws ec2 describe-images \
  --owner amazon \
  --filters 'Name=name,Values=Windows_Server-201*' \
  --query 'Images[].[CreationDate,ImageId,Name]' \
  --output text