diff --git a/partition.cpp b/partition.cpp
index aa82c09e..c2ad4bce 100644
--- a/partition.cpp
+++ b/partition.cpp
@@ -1128,6 +1128,7 @@ void TWPartition::Setup_Data_Media() {
 		DataManager::SetValue("tw_has_internal", 1);
 		DataManager::SetValue("tw_has_data_media", 1);
 		backup_exclusions.add_absolute_dir("/data/data/com.google.android.music/files");
+		backup_exclusions.add_absolute_dir("/data/per_boot"); // DJ9,14Jan2020 - exclude this dir to prevent "error 255" on AOSP ROMs that create and lock it
 		wipe_exclusions.add_absolute_dir(Mount_Point + "/misc/vold"); // adopted storage keys
 		ExcludeAll(Mount_Point + "/.layout_version");
 		ExcludeAll(Mount_Point + "/system/storage.xml");