diff --git a/code/nel/tools/pipeline/service/module_pipeline_master.cpp b/code/nel/tools/pipeline/service/module_pipeline_master.cpp
index ffbd748b6..b2e73a205 100644
--- a/code/nel/tools/pipeline/service/module_pipeline_master.cpp
+++ b/code/nel/tools/pipeline/service/module_pipeline_master.cpp
@@ -109,10 +109,10 @@ public:
 	{
 		if (moduleProxy->getModuleClassName() == "ModulePipelineSlave")
 		{
-			nlassert(m_Slaves.find(moduleProxy) == m_Slaves.end());
-
 			nlinfo("Slave UP (%s)", moduleProxy->getModuleName().c_str());
 			
+			nlassert(m_Slaves.find(moduleProxy) == m_Slaves.end());
+			
 			m_SlavesMutex.lock();
 
 			CSlave *slave = new CSlave(this, moduleProxy);
@@ -127,7 +127,9 @@ public:
 		if (moduleProxy->getModuleClassName() == "ModulePipelineSlave")
 		{
 			nlinfo("Slave DOWN (%s)", moduleProxy->getModuleName().c_str());
-
+			
+			nlassert(m_Slaves.find(moduleProxy) != m_Slaves.end());
+			
 			m_SlavesMutex.lock();
 
 			TSlaveMap::iterator slaveIt = m_Slaves.find(moduleProxy);