diff --git a/src/obi_ecopcr.c b/src/obi_ecopcr.c
old mode 100755
new mode 100644
index dbfa6cb..1d8dc3b
--- a/src/obi_ecopcr.c
+++ b/src/obi_ecopcr.c
@@ -105,7 +105,8 @@ static int create_output_columns(Obiview_p o_view, bool kingdom_mode);
  * @param o_temp1_column A pointer on the output column for the temperature for the first primer.
  * @param o_temp2_column A pointer on the output column for the temperature for the second primer.
  *
- * @retval 0 if the operation was successfully completed.
+ * @retval 0 if the sequence was skipped (taxid not found, warning printed).
+ * @retval 1 if the sequence was successfully printed to the output.
  * @retval -1 if an error occurred.
  *
  * @since July 2018
@@ -366,6 +367,17 @@ static int print_seq(Obiview_p i_view, Obiview_p o_view,
 
 	// TODO add check for primer longer than MAX_PAT_LEN (32)
 
+	// Get sequence id
+	seq_id = obi_get_str_with_elt_idx_and_col_p_in_view(i_view, i_id_column, i_idx, 0);
+
+	// Get the taxon structure
+	main_taxon = obi_taxo_get_taxon_with_taxid(taxonomy, taxid);
+	if (main_taxon == NULL)
+	{
+		obidebug(1, "\nWarning: error reading the taxonomic information of a sequence. Seq id: %s, taxid: %d. Probably deprecated taxid. Skipping this sequence.", seq_id, taxid);
+		return 0;
+	}
+
 	ldelta = (pos1 <= keep_nucleotides)?pos1:keep_nucleotides;
 	rdelta = ((pos2+keep_nucleotides)>=seq_len)?seq_len-pos2:keep_nucleotides;
 
@@ -432,18 +444,9 @@ static int print_seq(Obiview_p i_view, Obiview_p o_view,
 		tm2 = OBIFloat_NA;
 
 	// Write sequence id
-	seq_id = obi_get_str_with_elt_idx_and_col_p_in_view(i_view, i_id_column, i_idx, 0);
 	if (obi_set_str_with_elt_idx_and_col_p_in_view(o_view, o_id_column, o_idx, 0, seq_id) < 0)
 	{
-		obidebug(1, "\nError writing the sequence id (%s)", seq_id);
-		return -1;
-	}
-
-	// Get the taxon structure
-	main_taxon = obi_taxo_get_taxon_with_taxid(taxonomy, taxid);
-	if (main_taxon == NULL)
-	{
-		obidebug(1, "\nError reading the taxonomic information of a sequence, sequence id: %s, taxid: %d", seq_id, taxid);
+		obidebug(1, "\nError writing the sequence id");
 		return -1;
 	}
 
@@ -629,7 +632,7 @@ static int print_seq(Obiview_p i_view, Obiview_p o_view,
 		return -1;
 	}
 
-	return 0;
+	return 1;
 }
 
 
@@ -698,6 +701,7 @@ int obi_ecopcr(const char* i_dms_name,
 
 	obiint_t      taxid;
 	char*         sequence;
+	int			  printed;
 
 	SeqPtr        apatseq=NULL;
 	int32_t       o1Hits;
@@ -1072,7 +1076,7 @@ int obi_ecopcr(const char* i_dms_name,
 												(!max_len || (length <= max_len)))
 											{
 												// Print the found amplicon
-												if (print_seq(i_view, o_view,
+												printed = print_seq(i_view, o_view,
 														  	  i_idx, o_idx,
 															  taxonomy,
 															  sequence,
@@ -1098,12 +1102,14 @@ int obi_ecopcr(const char* i_dms_name,
 															  o_strand_column,
 															  o_primer1_column, o_primer2_column,
 															  o_error1_column, o_error2_column,
-															  o_temp1_column,  o_temp2_column) < 0)
+															  o_temp1_column,  o_temp2_column);
+												if (printed < 0)
 												{
 													obidebug(1, "\nError writing the ecopcr result");
 													return -1;
 												}
-												o_idx++;
+												else if (printed > 0)
+													o_idx++;
 											}
 										}
 									}
@@ -1160,7 +1166,7 @@ int obi_ecopcr(const char* i_dms_name,
 												(!max_len || (length <= max_len)))
 											{
 												// Print the found amplicon
-												if (print_seq(i_view, o_view,
+												printed = print_seq(i_view, o_view,
 														  	  i_idx, o_idx,
 															  taxonomy,
 															  sequence,
@@ -1186,12 +1192,14 @@ int obi_ecopcr(const char* i_dms_name,
 															  o_strand_column,
 															  o_primer1_column, o_primer2_column,
 															  o_error1_column, o_error2_column,
-															  o_temp1_column,  o_temp2_column) < 0)
+															  o_temp1_column,  o_temp2_column);
+												if (printed < 0)
 												{
 													obidebug(1, "\nError writing the ecopcr result");
 													return -1;
 												}
-												o_idx++;
+												else if (printed > 0)
+													o_idx++;
 											}
 										}
 									}