Unrelated to your question, but in the interests of improving your style you may find the following of interest:

#!/usr/bin/perl
use strict;

my $directory = "D:\\FTP-Accounts\\upload";
my $kMaxHours = 1;
my $count;

print "\n";
opendir my ($scan), $directory or die $!;

while (my $name = readdir($scan)) {
    #next unless (-f "$directory/$_");
    my $age = -M $name;

    print "$name - Days = $age\n";
    $age *= 24;

    if ($age > $kMaxHours) {
        ++$count;
        print " * Triggersed * Hours = $_\n\n";
    }
}

closedir $scan;
print "\nFile Count - $count -\n";

if (! $count) {
    print "OK:";
    exit 0;
}

print "\nWarning: file is older than $kMaxHours hours\n";
exit 1;
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Points to note:

• the k prefix in $kMaxHours as a convention to indicate a "constant"
• Use a lexical handle for the directory scan handle ($scan)
• use explicit variables instead of overuse of the default variable to make code easier to understand ($age, $name)
• Use early exit to avoid needless nested code and repeated tests (<c>if (! $count) ...

There may be other minor changes - can you spot them?