Your problem is that you are not checking for errors. Always use the following idiom to open files :

  open FILE, "< $filename" or die "Couldn't open $filename : $!\n";

  ... read file, do stuff ...

  close FILE;
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Not using "<" in the filename to specify a read operation also works, but it's better to be explicit in what you are doing.

Another thing to watch out for is specifying DOS filenames in Perl, as Perl will interpolate strings if they are double-quoted (you use " instead of '). Instead of using a backslash ("\") to separate directories, use a forward slash ("/"). This works under both, Unix and DOS and relieves you from having to quote your backslashes in your sourcecode.