diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/apps/AbstractProcessDialog.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/apps/AbstractProcessDialog.java
index 288813b913..b17068cd8a 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/apps/AbstractProcessDialog.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/apps/AbstractProcessDialog.java
@@ -820,15 +820,15 @@ public abstract class AbstractProcessDialog extends Window implements IProcessUI
 	
 	protected void startProcess()
 	{
+		if (!parameterPanel.validateParameters())
+			return;
+
 		if (m_pi.isProcessRunning(parameterPanel.getParameters())) {
 			FDialog.error(getWindowNo(), "ProcessAlreadyRunning");
 			log.log(Level.WARNING, "Abort process " + m_AD_Process_ID + " because it is already running");
 			return;
 		}
 
-		if (!parameterPanel.validateParameters())
-			return;
-		
 		startProcess0();
 	}