diff --git a/radio/src/bootloader/boot.cpp b/radio/src/bootloader/boot.cpp
index 6c4516156..6c534e8ec 100644
--- a/radio/src/bootloader/boot.cpp
+++ b/radio/src/bootloader/boot.cpp
@@ -664,6 +664,7 @@ int main()
           // Select file to flash
           state = ST_FLASH_CHECK;
           Valid = 0;
+          memset(Block_buffer, 0, sizeof(Block_buffer));
         }
         else if (event == EVT_KEY_FIRST(BOOT_KEY_EXIT)) {
           state = ST_START;