• Add use strict; and use warnings; - Make your code work with them.
• Simplify and print out

      print "$array[$i]\n";
      #open(FILE,"$array[$i]") or die "Could not open file :$!";
      # do something
      #close(FILE);
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open(FILE,"$_") or die " Could not open file :$! " ;
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In addition to everything else that has been said, the oft and rightly so repeated mantra is:

• use lexical filehandles;
• use the three args form of open;
• (include relevant info in the error message.)

To which I add: "$_" is called "useless use of quotes." Thus:

open my $file, '<', $_ or die "Could not open `$_': $!\n";
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