diff --git a/src/java/davmail/exchange/VCalendar.java b/src/java/davmail/exchange/VCalendar.java
index f030b7d1..2ad28570 100644
--- a/src/java/davmail/exchange/VCalendar.java
+++ b/src/java/davmail/exchange/VCalendar.java
@@ -179,6 +179,9 @@ public class VCalendar extends VObject {
                         // convert date values to outlook compatible values
                         setServerAllday(vObject.getProperty("DTSTART"));
                         setServerAllday(vObject.getProperty("DTEND"));
+                    } else {
+                        fixTzid(vObject.getProperty("DTSTART"));
+                        fixTzid(vObject.getProperty("DTEND"));
                     }
                 }
 
@@ -190,6 +193,12 @@ public class VCalendar extends VObject {
 
     }
 
+    private void fixTzid(VProperty property) {
+        if (property != null && !property.hasParam("TZID")) {
+            property.addParam("TZID", vTimezone.getPropertyValue("TZID"));
+        }
+    }
+
     protected void splitExDate(VObject vObject) {
         List<VProperty> exDateProperties = vObject.getProperties("EXDATE");
         if (exDateProperties != null) {
diff --git a/src/test/davmail/caldav/TestCaldav.java b/src/test/davmail/caldav/TestCaldav.java
index 7d95ff9c..3297db83 100644
--- a/src/test/davmail/caldav/TestCaldav.java
+++ b/src/test/davmail/caldav/TestCaldav.java
@@ -149,8 +149,6 @@ public class TestCaldav extends AbstractDavMailTestCase {
         MultiStatus multiStatus = method.getResponseBodyAsMultiStatus();
         MultiStatusResponse[] responses = multiStatus.getResponses();
 
-        Set<String> ITEM_PROPERTIES = new HashSet<String>();
-        ITEM_PROPERTIES.add("instancetype");
         List<ExchangeSession.Event> events = session.searchEvents("/users/" + session.getEmail() + "/calendar/",
                 session.and(
                         session.gt("dtstart", session.formatSearchDate(start)),
diff --git a/src/test/davmail/exchange/TestExchangeSessionEvent.java b/src/test/davmail/exchange/TestExchangeSessionEvent.java
index e862300b..dfafbf74 100644
--- a/src/test/davmail/exchange/TestExchangeSessionEvent.java
+++ b/src/test/davmail/exchange/TestExchangeSessionEvent.java
@@ -276,4 +276,16 @@ public class TestExchangeSessionEvent extends TestCase {
         System.out.println("'"+BundleMessage.format(status)+"'");
     }
 
+    public void testMissingTzid() throws IOException {
+        String itemBody = "BEGIN:VCALENDAR\n" +
+                "BEGIN:VEVENT\n" +
+                "DTSTART:20100101T000000\n" +
+                "DTEND:20100102T000000\n" +
+                "END:VEVENT\n" +
+                "END:VCALENDAR";
+        String toServer = fixICS(itemBody, false);
+        System.out.println(toServer);
+        assertTrue(toServer.contains("DTSTART;TZID="));
+        assertTrue(toServer.contains("DTEND;TZID="));
+    }
 }