No trick, you just assigning the wrong values to $original_file and $new_file.

To $original_file, you assign the string

\serv123\logs\log1.txt
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To $new_file, you assign the string

C:Documents and SettingsSerdesktop
ewfile.log
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Use use strict; use warnings;!!!

The following string literals will produce the strings you want:

my $original_file = '\\\\serv123\\logs\\log1.txt';
my $new_file = "C:\\Documents and Settings\\user\\desktop\\newfile.log
+";
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