diff --git a/libs/ardour/ardour/filename_extensions.h b/libs/ardour/ardour/filename_extensions.h
index 6d50de6570..a664e0f83b 100644
--- a/libs/ardour/ardour/filename_extensions.h
+++ b/libs/ardour/ardour/filename_extensions.h
@@ -35,6 +35,7 @@ namespace ARDOUR {
 	LIBARDOUR_API extern const char* const export_preset_suffix;
 	LIBARDOUR_API extern const char* const export_format_suffix;
 	LIBARDOUR_API extern const char* const session_archive_suffix;
+	LIBARDOUR_API extern const char* const template_archive_suffix;
 
 }
 
diff --git a/libs/ardour/filename_extensions.cc b/libs/ardour/filename_extensions.cc
index 31f07d5578..fe83b18a4f 100644
--- a/libs/ardour/filename_extensions.cc
+++ b/libs/ardour/filename_extensions.cc
@@ -32,6 +32,7 @@ const char* const temp_suffix = X_(".tmp");
 const char* const history_suffix = X_(".history");
 const char* const export_preset_suffix = X_(".preset");
 const char* const export_format_suffix = X_(".format");
-const char* const session_archive_suffix = X_(".ardourzip");
+const char* const session_archive_suffix = X_(".ardour-session-archive");
+const char* const template_archive_suffix = X_(".ardour-template-archive");
 
 }
diff --git a/libs/ardour/find_session.cc b/libs/ardour/find_session.cc
index 75339c9f51..7644422f6f 100644
--- a/libs/ardour/find_session.cc
+++ b/libs/ardour/find_session.cc
@@ -262,7 +262,7 @@ string inflate_error (int e) {
 		case 0:
 			return _("No Error");
 		case 1:
-			return _("File extension is not .tar.xz");
+			return string_compose (_("File extension is not %1"), session_archive_suffix);
 		case 2:
 			return _("Archive is empty");
 		case 3: