To monitor client system file monitoring

When 3 clients are connected wtih server. I want to monitor file, after threshold has been setup.

ForExample:
 Threshold is 50% has been set.
Iam monitoring folder name as C:\Newfolder. 
Total Size of NewFolder is 500MB.
When Newfolder reaches 250MB, I want to send notification to IT Team.

How it can be achieved. This is new to me.

I have done this sample in windows service. but we cannot install windows service in N number of client system.

public void FolderMonitorTimer()
       {
           timer.Elapsed += new ElapsedEventHandler(OnElapsedTime);
           timer.Interval = 5000;
           timer.Enabled = true;
       }

<pre>// Get current system File monitor

static long DirectorySize12(DirectoryInfo dInfo, bool includeSubDir)
      {
          // Enumerate all the files
          long totalSize = dInfo.EnumerateFiles()
                       .Sum(file => file.Length);

          // If Subdirectories are to be included
          if (includeSubDir)
          {
              // Enumerate all sub-directories
              totalSize += dInfo.EnumerateDirectories()
                       .Sum(dir => DirectorySize12(dir, true));
          }
          return totalSize;
      }

private void OnElapsedTime(object source, ElapsedEventArgs e)
     {
         DirectoryInfo dInfo = new DirectoryInfo(FolderPath);

         long sizeOfDir = DirectorySize12(dInfo, true);


         usedSizeMB = ((double)sizeOfDir) / (1024 * 1024);
         availSizeMB = strDiskDefaultSize - usedSizeMB;
         availPercent = availSizeMB / strDiskDefaultSize * 100;
         UsedPercent = usedSizeMB / strDiskDefaultSize * 100;
         timer.Interval = 1000;
         WarningThreshold= 50;

         if ((Convert.ToInt32(UsedPercent) > Convert.ToInt32(WarningThreshold)))
         {
             //Send notification to IT Team

         }