diff --git a/stratosphere/ams_mitm/source/amsmitm_initialization.cpp b/stratosphere/ams_mitm/source/amsmitm_initialization.cpp
index 405a43cc1..6ed3acd0b 100644
--- a/stratosphere/ams_mitm/source/amsmitm_initialization.cpp
+++ b/stratosphere/ams_mitm/source/amsmitm_initialization.cpp
@@ -64,6 +64,10 @@ namespace ams::mitm {
         /* Emummc file protection. */
         FsFile g_emummc_file;
 
+        /* Maintain exclusive access to the fusee-secondary archive. */
+        FsFile g_secondary_file;
+        FsFile g_sept_payload_file;
+
         constexpr inline bool IsHexadecimal(const char *str) {
             while (*str) {
                 if (std::isxdigit(static_cast<unsigned char>(*str))) {
@@ -129,6 +133,15 @@ namespace ams::mitm {
                 R_ABORT_UNLESS(fsFileWrite(&g_bis_key_file, 0, bis_keys, sizeof(bis_keys), FsWriteOption_Flush));
                 /* NOTE: g_bis_key_file is intentionally not closed here.  This prevents any other process from opening it. */
             }
+
+            /* Open a reference to the fusee-secondary archive. */
+            /* As upcoming/current atmosphere releases will contain more than one zip which users much choose between, */
+            /* maintaining an open reference prevents cleanly the issue of "automatic" updaters selecting the incorrect */
+            /* zip, and encourages good updating hygiene -- atmosphere should not be updated on SD while HOS is alive. */
+            {
+                R_ABORT_UNLESS(mitm::fs::OpenSdFile(std::addressof(g_secondary_file),    "/atmosphere/fusee-secondary.bin", ams::fs::OpenMode_ReadWrite));
+                R_ABORT_UNLESS(mitm::fs::OpenSdFile(std::addressof(g_sept_payload_file), "/sept/payload.bin",               ams::fs::OpenMode_ReadWrite));
+            }
         }
 
         /* Initialization implementation */