diff --git a/Server/Forms/FrmReverseProxy.cs b/Server/Forms/FrmReverseProxy.cs
index d3365cba..19ec0ed1 100644
--- a/Server/Forms/FrmReverseProxy.cs
+++ b/Server/Forms/FrmReverseProxy.cs
@@ -110,7 +110,7 @@ private void FrmReverseProxy_FormClosing(object sender, FormClosingEventArgs e)
 
             for (int i = 0; i < _clients.Length; i++)
             {
-                if (_clients[i].Value != null)
+                if (_clients[i] != null && _clients[i].Value != null)
                     _clients[i].Value.FrmProxy = null;
             }
         }