http://www.perlmonks.org?node_id=821641


in reply to YAML Parsing Errors Using CPAN on Windows

I had the same problem. The solution was to make CPAN stop loading YAML, but I don't remember exactly how. Here's what o conf shows me for yaml vars:
yaml_load_code [undef] yaml_module []
I don't know how to undef a value from within CPAN, and perldoc isn't helpful for the shell, but I assume somebody here knows. As a last resort you could edit CPAN.pm. And don't forget to o conf commit to write any changes to disk from within the CPAN shell.