diff --git a/src/java/davmail/caldav/CaldavConnection.java b/src/java/davmail/caldav/CaldavConnection.java
index 6afa8261..d28a86b4 100644
--- a/src/java/davmail/caldav/CaldavConnection.java
+++ b/src/java/davmail/caldav/CaldavConnection.java
@@ -721,9 +721,7 @@ public class CaldavConnection extends AbstractConnection {
             response.appendHrefProperty("C:calendar-user-address-set", "mailto:" + actualPrincipal);
         }
 
-        // no inbox/outbox for delegated/shared calendars
-        // case insensitive to avoir "response..*::["schedule-inbox-URL"]..*::href[0] is undefined" error in Lightning
-        if ("users".equals(prefix) && session.getEmail().equalsIgnoreCase(principal)) {
+        if ("users".equals(prefix)) {
             if (request.hasProperty("schedule-inbox-URL")) {
                 response.appendHrefProperty("C:schedule-inbox-URL", "/users/" + actualPrincipal + "/inbox");
             }