Please don't ignore the formatting guidelines, this obviously looked wrong when you previewed the post. Your code:

#use 5.010;
use strict;

use strict; 
my $modified_within = 60 * 2; # 2 minutes 
my $size_limit = 1024 * 1024 * 2; # 2 MB 
my $OPCMSG = "C:\Program Files\HP\HP BTO Software\bin\win64\OpC\opcmsg
+.exe"; 
my $file = "H:\\Program Data\\HP\\HP BTO Software\\shared\\tmp\\queues
+\\MsgQueue"; 

if ([stat $file]->[9] > time - $modified_within){ 
    if (-s $file > $size_limit) { 
        print "File is recent, and over size limit"; 
    } else { 
        print "File is recent, but not over size limit"; 
        $OPCMSG a=OM9 o=failover s=normal mag_t="Hello!! I am fine, ho
+pe you are doing well";
    }
} else { 
    print "File is not recent"; 
}
[download]

I notice you ignored my previous advice to test that files exist, resulting in "File is not recent" being displayed for non existent files. Where did you copy and past this line from?

$OPCMSG a=OM9 o=failover s=normal mag_t="Hello!! I am fine, hope you a
+re doing well";
[download]

And more to the point what do you expect it to do? A sensible guess would be that you expect to run opsmsg.exe with these arguments, but you've no idea how to do so and expect people to work through your messed up code and work out what you're trying to do. Don't make posts hard to read with regards formatting, and explain exactly what you're trying to achieve. Making people guess what you expect your hard to read code is doing is a bad strategy. Don't copy and paste code you found/were given online without any understanding of what it does.

To achieve what you want see the example under system. If you're actually interested in learning Perl I suggest you invest the time reading:

• PerlMonks for the Absolute Beginner
• perlintro
• Perl FAQ
• http://learn.perl.org
• http://perldoc.perl.org
• Browse the Tutorials section of this site.
• #11900 You cannot just paste code with no understanding of what is going on and expect it to work.