diff --git a/SecureAgentParameters.cs b/SecureAgentParameters.cs
index 33e7ac5..1cb9f88 100644
--- a/SecureAgentParameters.cs
+++ b/SecureAgentParameters.cs
@@ -537,8 +537,10 @@ public void UpdateDiscoveryValues(SnmpPacket packet)
 				_engineTime.Value = pkt.USM.EngineTime;
 				_engineBoots.Value = pkt.USM.EngineBoots;
 				UpdateTimeStamp();
-				_contextEngineId.Set(pkt.ScopedPdu.ContextEngineId);
-				_contextName.Set(pkt.ScopedPdu.ContextName);
+				if (_contextEngineId.Length == 0)
+					_contextEngineId.Set(pkt.ScopedPdu.ContextEngineId);
+				if (_contextName.Length == 0)
+					_contextName.Set(pkt.ScopedPdu.ContextName);
 			}
 			else
 				throw new SnmpInvalidVersionException("Invalid SNMP version.");
diff --git a/UTarget.cs b/UTarget.cs
index b23bc85..0fc2589 100644
--- a/UTarget.cs
+++ b/UTarget.cs
@@ -317,8 +317,10 @@ public void UpdateDiscoveryValues(SnmpPacket packet)
 				_engineTime.Value = pkt.USM.EngineTime;
 				_engineBoots.Value = pkt.USM.EngineBoots;
 				UpdateTimeStamp();
-				_contextEngineId.Set(pkt.ScopedPdu.ContextEngineId);
-				_contextName.Set(pkt.ScopedPdu.ContextName);
+				if (_contextEngineId.Length == 0)
+					_contextEngineId.Set(pkt.ScopedPdu.ContextEngineId);
+				if (_contextName.Length == 0)
+					_contextName.Set(pkt.ScopedPdu.ContextName);
 			}
 			else
 				throw new SnmpInvalidVersionException("Invalid SNMP version.");