Resolve the message 'The environment must be purely alphanumeric, not 'puppet-ca' on Windows nodes in Puppet Enterprise

When you manually run Puppet in a command line instance on a Windows node you get The environment must be purely alphanumeric, not 'puppet-ca' error message, and the Puppet run won't do anything. However, the Puppet agent service (including automatic Puppet runs) is working without any issues.

Error messages and logs

When you run puppet agent -t in a command line instance on a Windows node, you get the following error messages:

Error: Could not request certificate: Error 400 on SERVER: The environment must be purely alphanumeric, not 'puppet-ca'

Exiting; failed to retrieve certificate and waitforcert is disabled

Usually, when you get the error message The environment must be purely alphanumeric, not '<some_string>', it means that one or more of your environment names contain illegal characters (characters that are not A-Z, a-z, 0-9, or _ (underscore)).

However, on a Windows node, when the error message is The environment must be purely alphanumeric, not 'puppet-ca', the command line instance does not have sufficient privileges to complete a Puppet run.

Version and installation information

PE version: All supported versions
OS: Windows

Solution

Open a new command line instance with administrator privileges and run: puppet agent -t