diff --git a/j2ee.common/src/org/netbeans/modules/j2ee/common/J2eeProjectCapabilities.java b/j2ee.common/src/org/netbeans/modules/j2ee/common/J2eeProjectCapabilities.java
--- a/j2ee.common/src/org/netbeans/modules/j2ee/common/J2eeProjectCapabilities.java
+++ b/j2ee.common/src/org/netbeans/modules/j2ee/common/J2eeProjectCapabilities.java
@@ -128,6 +128,11 @@
                 && platform.isToolSupported("defaultPersistenceProviderJavaEE5"); // NOI18N
     }
 
+    public boolean isServerInstanceSet() {
+        return getPlatform() != null;
+    }
+
+
     private J2eePlatform getPlatform() {
         try {
             String instance = provider.getServerInstanceID();
diff --git a/j2ee.ejbjarproject/src/org/netbeans/modules/j2ee/ejbjarproject/EjbJarJPAModuleInfo.java b/j2ee.ejbjarproject/src/org/netbeans/modules/j2ee/ejbjarproject/EjbJarJPAModuleInfo.java
--- a/j2ee.ejbjarproject/src/org/netbeans/modules/j2ee/ejbjarproject/EjbJarJPAModuleInfo.java
+++ b/j2ee.ejbjarproject/src/org/netbeans/modules/j2ee/ejbjarproject/EjbJarJPAModuleInfo.java
@@ -41,6 +41,7 @@
 
 package org.netbeans.modules.j2ee.ejbjarproject;
 
+import org.netbeans.modules.j2ee.common.J2eeProjectCapabilities;
 import org.netbeans.modules.j2ee.persistence.spi.moduleinfo.JPAModuleInfo;
 
 /**
@@ -64,4 +65,10 @@
         return project.getEjbModule().getModuleVersion();
     }
 
+    @Override
+    public boolean isServerInstanceSet() {
+        return J2eeProjectCapabilities.forProject(project).isServerInstanceSet();
+    }
+
+
 }
diff --git a/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/spi/moduleinfo/JPAModuleInfo.java b/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/spi/moduleinfo/JPAModuleInfo.java
--- a/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/spi/moduleinfo/JPAModuleInfo.java
+++ b/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/spi/moduleinfo/JPAModuleInfo.java
@@ -69,5 +69,7 @@
      * @return the version number of the module.
      */ 
     String getVersion();
+
+    boolean isServerInstanceSet();
     
 }
diff --git a/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/Util.java b/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/Util.java
--- a/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/Util.java
+++ b/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/Util.java
@@ -226,6 +226,18 @@
         return Util.isSupportedJavaEEVersion(project) && providerSupplier != null && providerSupplier.supportsDefaultProvider();
     }
 
+    /** Returns true if the project represents a Java EE project (not Java SE), which does
+     * not have a server instance set. This could be e.g. a Maven project without a server set,
+     * or Ant project with broken server reference.
+     */
+    public static boolean isServerInstanceMissing(Project project) {
+        JPAModuleInfo moduleInfo = project.getLookup().lookup(JPAModuleInfo.class);
+        if (moduleInfo == null) {
+            return false;
+        }
+        return !moduleInfo.isServerInstanceSet();
+    }
+
     public static Provider getDefaultProvider(Project project) {
         PersistenceProviderSupplier providerSupplier = project.getLookup().lookup(PersistenceProviderSupplier.class);
         return (providerSupplier != null && providerSupplier.supportsDefaultProvider()) ? providerSupplier.getSupportedProviders().get(0) : null;
diff --git a/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/unit/PersistenceUnitWizardPanelJdbc.java b/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/unit/PersistenceUnitWizardPanelJdbc.java
--- a/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/unit/PersistenceUnitWizardPanelJdbc.java
+++ b/j2ee.persistence/src/org/netbeans/modules/j2ee/persistence/wizard/unit/PersistenceUnitWizardPanelJdbc.java
@@ -61,6 +61,7 @@
 import org.netbeans.modules.j2ee.persistence.provider.ProviderUtil;
 import org.netbeans.modules.j2ee.persistence.util.PersistenceProviderComboboxHelper;
 import org.netbeans.modules.j2ee.persistence.util.SourceLevelChecker;
+import org.netbeans.modules.j2ee.persistence.wizard.Util;
 import org.netbeans.modules.j2ee.persistence.wizard.unit.PersistenceUnitWizardPanel.TableGeneration;
 import org.openide.util.ImageUtilities;
 import org.openide.util.NbBundle;
@@ -210,6 +211,11 @@
                     }
             }
         }
+        if (warning == null) {
+            if (Util.isServerInstanceMissing(project)) {
+                warning = "You should set the server!";
+            }
+        }
         ImageIcon icon = null;
         if(warning != null){
             icon = ImageUtilities.loadImageIcon("org/netbeans/modules/j2ee/persistence/ui/resources/warning.gif", false); //NOI18N
diff --git a/maven.j2ee/src/org/netbeans/modules/maven/j2ee/JPAStuffImpl.java b/maven.j2ee/src/org/netbeans/modules/maven/j2ee/JPAStuffImpl.java
--- a/maven.j2ee/src/org/netbeans/modules/maven/j2ee/JPAStuffImpl.java
+++ b/maven.j2ee/src/org/netbeans/modules/maven/j2ee/JPAStuffImpl.java
@@ -47,8 +47,11 @@
 import org.netbeans.modules.maven.j2ee.ejb.*;
 import org.netbeans.api.project.Project;
 import org.netbeans.modules.j2ee.common.DatasourceUIHelper;
+import org.netbeans.modules.j2ee.common.J2eeProjectCapabilities;
 import org.netbeans.modules.j2ee.deployment.common.api.ConfigurationException;
 import org.netbeans.modules.j2ee.deployment.common.api.Datasource;
+import org.netbeans.modules.j2ee.deployment.devmodules.api.Deployment;
+import org.netbeans.modules.j2ee.deployment.devmodules.api.InstanceRemovedException;
 import org.netbeans.modules.j2ee.deployment.devmodules.spi.J2eeModuleProvider;
 import org.netbeans.modules.j2ee.persistence.spi.datasource.JPADataSource;
 import org.netbeans.modules.j2ee.persistence.spi.datasource.JPADataSourcePopulator;
@@ -130,6 +133,21 @@
         return null;
     }
 
+    @Override
+    public boolean isServerInstanceSet() {
+        return J2eeProjectCapabilities.forProject(project).isServerInstanceSet();
+//        J2eeModuleProvider; prvd = project.getLookup().lookup(J2eeModuleProvider.class);
+//        if (prvd == null) {
+//            return false;
+//        }
+//        try {
+//            return Deployment.getDefault().
+//                getServerInstance(prvd.getServerInstanceID()).getJ2eePlatform() != null;
+//        } catch (InstanceRemovedException e) {
+//            return false;
+//        }
+    }
+
 
     /**
      * Provides <code>JPADataSource</code> interface for <code>Datasource</code>s.
diff --git a/web.project/src/org/netbeans/modules/web/project/WebJPAModuleInfo.java b/web.project/src/org/netbeans/modules/web/project/WebJPAModuleInfo.java
--- a/web.project/src/org/netbeans/modules/web/project/WebJPAModuleInfo.java
+++ b/web.project/src/org/netbeans/modules/web/project/WebJPAModuleInfo.java
@@ -41,6 +41,7 @@
 
 package org.netbeans.modules.web.project;
 
+import org.netbeans.modules.j2ee.common.J2eeProjectCapabilities;
 import org.netbeans.modules.j2ee.persistence.spi.moduleinfo.JPAModuleInfo;
 import org.netbeans.modules.j2ee.persistence.spi.moduleinfo.JPAModuleInfo.ModuleType;
 
@@ -67,4 +68,10 @@
         return project.getWebModule().getModuleVersion();
     }
 
+    @Override
+    public boolean isServerInstanceSet() {
+        return J2eeProjectCapabilities.forProject(project).isServerInstanceSet();
+    }
+
+
 }