Did you Super Search before posting? See Net::SSH::Perl script in windows - getpwuid is unimplemented (again Super Search or google for more examples), you've also not posted any code for anyone to look at. Read and understand How do I post a question effectively?.

Update: Are we to assume that this relates to run a perl script on a unix machine from a win machine?

The code is fairly simple - given a file - $basename

if (-e $basename)
{
$attrs = stat($basename);
my $fileOwnerID = $attrs->uid;
$fileOwner = (getpwuid $fileOwnerID)[0];
#$fileOwner = sprintf "%s",stat($basename)->uid;
my $groupID = $attrs->gid;
$groupName = (getgrgid $groupID)[0];
}
[download]

So if getpwuid is not implemented or cannot be used in Windows...how do I get the name of the owner of a file ?

"The code is fairly simple"

In future, as described in How do I post a question effectively? consider posting a minimal example which demonstrates the problem in your first post, rather than people having to draw information from you piece meal. I suggest you actually google search getptuid to find out what it is, and why it doesn't work on your platform.

But it works fine in HPUX environment. Thanks !!!

Well, Windows XP is not HPUX, and like the message tells you The getpwuid function is unimplemented