It would be nice to see the corrected code - I also spotted a syntax error ($success is set inside the if, but then you use $sucess, with one less "c"). You could also put the print line before the rename, just to be sure that you're doing the right thing (note the brackets, just to be sure that there are no spaces):

#....
print "About to rename [$path] to [$target]\n";
rename ($path,$target) or die "Could not rename: $!";
#...
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Moreover, you're probably on some kind of Win32 platform. Are you sure that the file you're trying to rename isn't open by some other application that is "locking" it?