Puppet solve invalid byte sequence in us Ascii

When you run "puppet agent" and get

Error: Could not retrieve catalog from remote server: Error 400 on SERVER: invalid byte 
sequence in US-ASCII at /etc/puppet/modules/vendor/

or run "puppet apply" and get

Error: Could not retrieve catalog from remote server: Error 400 on SERVER: Could not 
parse for environment production: invalid byte sequence in US-ASCII at /etc/puppet/manifests/someclass.pp:1

then the root case is probably the currently configured locale. Check the effective Ruby locale with

ruby -e 'puts Encoding.default_external'

Ensure that it returns a UTF-8 capable locale, if needed set it and rerun Puppet:

export LANG=de_DE.utf-8
export LC_ALL=de_DE.utf-8