Try adding the s modifier to the regex match in the while loop. Also you might want to use $/ instead of a literal \n as it's more portable. Although this code should do the job without having to loop through the string. 
$lines =~ s{$/$/}{$/}gs;

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HTH

_________
broquaint

In reply to Re: remove blank lines with regex by broquaint
in thread remove blank lines with regex by amarceluk

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