You're using system() incorrectly, specifically its return value. The error message is misleading, $! contains junk from a previous system call. Using system() correctly is very difficult, have a peek at the official documentation. All Perl built-ins suck, this one sucks the most.

Instead use autodie for proper error handling, it's tested and you get nice default error messages:

use autodie qw(:all);   # replaces system()
system $command;        # implicit error handler
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