diff --git a/src/ContactEdit.tsx b/src/ContactEdit.tsx
index 78dd13b..0f7ee89 100644
--- a/src/ContactEdit.tsx
+++ b/src/ContactEdit.tsx
@@ -226,6 +226,7 @@ class ContactEdit extends React.Component {
 
     let comp = contact.comp;
     comp.updatePropertyWithValue('prodid', '-//iCal.js EteSync Web');
+    comp.updatePropertyWithValue('version', '4.0');
     comp.updatePropertyWithValue('uid', this.state.uid);
     comp.updatePropertyWithValue('fn', this.state.fn);
 
diff --git a/src/pim-types.tsx b/src/pim-types.tsx
index 55be069..bebe578 100644
--- a/src/pim-types.tsx
+++ b/src/pim-types.tsx
@@ -22,6 +22,7 @@ export class EventType extends ICAL.Event {
   toIcal() {
     let comp = new ICAL.Component(['vcalendar', [], []]);
     comp.updatePropertyWithValue('prodid', '-//iCal.js EteSync Web');
+    comp.updatePropertyWithValue('version', '4.0');
 
     comp.addSubcomponent(this.component);
     return comp.toString();