diff --git a/source/installer.c b/source/installer.c
index 2038a79..ca1e161 100755
--- a/source/installer.c
+++ b/source/installer.c
@@ -72,7 +72,7 @@ static inline void installer(u32 a9lhBoot)
         path = "a9lh/otp.bin";
         if(fileRead((void *)OTP_OFFSET, path) != 256)
         {
-            u8 zeroes[256] = {0};
+            const u8 zeroes[256] = {0};
             if(memcmp((void *)OTP_FROM_MEM, zeroes, 256) == 0)
                 shutdown(1, "Error: otp.bin doesn't exist and can't be dumped");
 
@@ -149,6 +149,10 @@ static inline void installer(u32 a9lhBoot)
     if(!size || size > MAX_STAGE1_SIZE)
         shutdown(1, "Error: payload_stage1.bin doesn't exist or\nexceeds max size");
 
+    const u8 zeroes[688] = {0};
+    if(memcmp(zeroes, (void *)STAGE1_OFFSET, 688) == 0)
+        shutdown(1, "Error: the payload_stage1.bin you're attempting\nto install is not compatible");
+
     //Read stage2
     memset32((void *)STAGE2_OFFSET, 0, MAX_STAGE2_SIZE);
     path = "a9lh/payload_stage2.bin";