diff --git a/xorriso/iso_img.c b/xorriso/iso_img.c
index b9712968..8dd7c420 100644
--- a/xorriso/iso_img.c
+++ b/xorriso/iso_img.c
@@ -1673,6 +1673,7 @@ static int Xorriso_scan_report_lines(struct XorrisO *xorriso,
  char **app_pseudo_paths= NULL;
  struct tm tm_erg;
  int was_force_bootable= 0;
+ uint64_t gpt_bheader_block= 0;
 
  struct mbr_par {
    uint8_t ptype;
@@ -1928,6 +1929,9 @@ static int Xorriso_scan_report_lines(struct XorrisO *xorriso,
      idx= num[0] - 1;
      mbrpts[idx].has_path= 1;
 
+   } else if(strcmp(name, "GPT lba range      :") == 0) {
+     gpt_bheader_block= num[2];
+
    } else if(strcmp(name, "GPT type GUID      :") == 0) {
      idx= num[0] - 1;
      if(strcmp(textpt, "a2a0d0ebe5b9334487c068b6b72699c7") == 0)
@@ -1976,8 +1980,15 @@ static int Xorriso_scan_report_lines(struct XorrisO *xorriso,
    }
  }
 
- if(!have_protective_msdos)
-   appended_as_gpt= 0;
+ if(appended_as_gpt && !have_protective_msdos) {
+   if(mbr_count != 1) {
+     appended_as_gpt= 0;
+   } else if(mbrpts[0].ptype != 0xee || mbrpts[0].start_block != 1) {
+     appended_as_gpt= 0;
+   } else if(gpt_bheader_block != mbrpts[0].block_count) {
+     appended_as_gpt= 0;
+   }
+ }
 
  iso_part_blocks= img_blocks;
  for(mbr_idx = 0; mbr_idx < mbr_count; mbr_idx++) {
@@ -2184,7 +2195,7 @@ static int Xorriso_scan_report_lines(struct XorrisO *xorriso,
      else
        part_type= 0xcd;
 
-     if(high_block < num[1] && num[2] > 0 && !gpts[idx].is_gap) {
+     if(high_block * 4 < num[1] && num[2] > 0 && !gpts[idx].is_gap) {
        for(mbr_idx = 0; mbr_idx < mbr_count; mbr_idx++) {
          if(mbrpts[mbr_idx].start_block == num[1]) {
            if(mbrpts[mbr_idx].block_count != num[2] && !(flag & 1)) {
diff --git a/xorriso/xorriso_timestamp.h b/xorriso/xorriso_timestamp.h
index 6081e6be..551d6400 100644
--- a/xorriso/xorriso_timestamp.h
+++ b/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2018.09.09.130316"
+#define Xorriso_timestamP "2018.09.12.113255"