"Actuall in windows this programme is working fine But at the same time When I am trying this programme in windows it's not working and one more thing when i exectue my perl script in windows it's got stuck in cmd but after that when i prees enetr two or three time it will throw thius error " the system cannot" only these three word please check this if it's possible ..."
So it's working fine, apart from the fact that it doesn't work?
$y_date= `date --date="yesterday"`;
had you actually run this from the command prompt you'd notice that you're being prompted for user input, hence pressing enter multiple times provides the (invalid) input. The error you get isn't from your perl code, its because you don't understand what date does. As Corion suggested, don't reply on an external program (albeit the wrong program, which you don't seem to understand how to use) to get yesterdays date.