```{eval-rst}
.. image:: ../../images/cropped-plus3it-logo-cmyk.png
   :width: 140px
   :alt: Powered by Plus3 IT Systems
   :align: right
   :target: https://www.plus3it.com
```
<br>

# 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
```