diff --git a/server/mailserver/mail/mailmgr.go b/server/mailserver/mail/mailmgr.go
index d2656cf7..7fdba708 100644
--- a/server/mailserver/mail/mailmgr.go
+++ b/server/mailserver/mail/mailmgr.go
@@ -16,6 +16,7 @@ type userMail struct {
 }
 
 type userGroup struct {
+	groupId int64
 	mailHash map[int64]*mail
 	userHash map[string]int32
 }