diff --git a/openbis/dist/admin/upgrade.sh b/openbis/dist/admin/upgrade.sh
index baea62224a17cfbaa8780231264e1430765123bf..bef89228a98620513d6b136c8a699b6cdca39557 100755
--- a/openbis/dist/admin/upgrade.sh
+++ b/openbis/dist/admin/upgrade.sh
@@ -11,7 +11,7 @@ source $BASE/env
 
 ROOT_DIR=$BASE/../servers
 
-NOW=`date +%y%m%d-%H%m`
+NOW=`date +%y%m%d-%H%M`
 BACKUP_DIR=$BASE/../backup/$NOW
 
 $BASE/alldown.sh