Index: DamClients/DamUI/trunk/src/Dam/Forms/DamPlugin.cs
===================================================================
diff -u -r4954 -r4978
--- DamClients/DamUI/trunk/src/Dam/Forms/DamPlugin.cs	(.../DamPlugin.cs)	(revision 4954)
+++ DamClients/DamUI/trunk/src/Dam/Forms/DamPlugin.cs	(.../DamPlugin.cs)	(revision 4978)
@@ -37,6 +37,7 @@
 using Deltares.Dam.Data.Sensors;
 using Deltares.Dam.Data.UISupport;
 using Deltares.Dam.Forms.Properties;
+using Deltares.DamEngine.Data.Standard;
 using Deltares.DamEngine.Interface;
 using Deltares.DamEngine.Io;
 using Deltares.DamEngine.Io.XmlInput;
@@ -54,6 +55,7 @@
 using Deltares.Standard.IO.Xml;
 using Deltares.Standard.Language;
 using Deltares.Standard.Logging;
+using Deltares.Standard.Specifications;
 using DevExpress.XtraBars;
 using DevExpress.XtraEditors.Controls;
 using DevExpress.XtraEditors.Repository;
@@ -753,6 +755,10 @@
                 // do calculate. For now, just check length
                 if (string.IsNullOrEmpty(validationMessages))
                 {
+                    // Temporarily disable multicore calculation
+                    ThrowHelper.ThrowWhenConditionIsTrue<ValidationException>(
+                        "Multicore is currently not supported. Change number of cores to 1 in Tools menu.", () => damEngineInterface.DamProjectData.MaxCalculationCores > 1);
+
                     // only if validation is ok, then
                     string outputXml = damEngineInterface.Run();
                     Output output = DamXmlSerialization.LoadOutputFromXmlString(outputXml);