No, YAML is not installed.

Something is wrong and it has to do with permissions. Maybe its your umask, maybe its permissions on the directory /Users/Erika/.cpan/build/, or ..... but for some reason you cannot read /Users/Erika/.cpan/build/YAML-0.71-pZsez6/META.yml. Try checking to see what the permissions on /Users/Erika/.cpan/build/YAML-0.71-pZsez6/META.yml are.

Next thing I would do is take cpan out of the equation and try cpanp i YAML, if that doesn't work, I'd do it manually, ie

$ cd ~/tmp
wget -c http://search.cpan.org/CPAN/authors/id/A/AD/ADAMK/YAML-0.71.ta
+r.gz
tar -zxvf YAML-0.71.tar.gz
cd YAML-0.71
perl Makefile.PL
make
make test
make install
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