I have this working with both Win32::Process and backticks.. my code looks a lilttle like this...

Win32::Process::Create($ProcObj,
        "$xcall_path/bin/$prog",
        "$prog \"$type\" \"$file\" \"$call_num\"",
        0, # Don't inherit.
        NORMAL_PRIORITY_CLASS,
        ".") or &Update_Log("DEBUG - Cannot Launch the Service Desk Pr
+ocess process in the Log Call Routine: $!\n$prog\"$type\" \"$file\" \
+"$call_num\"\n");
    if ($ProcObj->Wait (180*1000)){
        # execution of the process is successfully.
        $ProcObj->Kill(0);
    } else {
        # process has hung up for some reason
        $ProcObj->Kill(255);
        $rc = 0;
    }
[download]

to get the path (ie $xcall_path I had to do something like so..

my $path     = "$ENV{'MYSYSENV'}\\X-CallLogger";
    unless ($xcall_path = Win32::GetShortPathName($path)) {
        &Event(EVENTLOG_ERROR_TYPE, "$0 - Path Problems in Setup for $
+path: $^E\n");
        return(0);
    }

    $xcall_path     =~s /\\/\//g;        #Substitute backslashes with 
+frontslashes
    $prog = $ARGV[0];
[download]

As I said I have had no problems with this. Perhaps look at the substitues of \'s with /'s

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