diff --git a/server/mailserver/mail/mail.go b/server/mailserver/mail/mail.go
index 4b6bb950..1d577ed0 100644
--- a/server/mailserver/mail/mail.go
+++ b/server/mailserver/mail/mail.go
@@ -2,6 +2,7 @@ package mail
 
 import (
 	"f5"
+	"sync"
 	//"main/common"
 	//"main/constant"
 	//"q5"
@@ -23,7 +24,7 @@ type mail struct {
 	userRegStart int32
 	userRegEnd int32
 	attachments []*attachment
-	userGroups []int64
+	userGroups *sync.Map
 	reciver string
 }