The file is located in the same folder as MyService.pl

That's irrelevant. What matters with where the file is located relative to the current directory (assuming you're relying on . in @INC). You can synchronize the two by adding the following at the top of your script.

use File::Basename        qw( dirname );
use File::Spec::Functions qw( rel2abs );
BEGIN { chdir(dirname(rel2abs($0))); }
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Or like you said, you can tell Perl where to look by adding the following at the top of your script.

use File::Basename        qw( dirname );
use File::Spec::Functions qw( rel2abs );
use lib dirname(rel2abs($0));
[download]

Note that FindBin does funky stuff, thus its absence from the above snippets.