diff --git a/barrOs_library.py b/barrOs_library.py
index 0f27ce2b7b56bef26885149d5eb78c384a8784c4..48b6cb2baccb1c1745c1eeb0540249835ca73617 100644
--- a/barrOs_library.py
+++ b/barrOs_library.py
@@ -2350,12 +2350,15 @@ def run_barros(arguments, offset = 1, step = 2, local_angle_threshold = 25, max_
             pdb_file = pdbID
             chains_inpdb = get_chains_in_pdb(pdb_file, source_pdb=False)[0]
 
-            try:
-                pdbID, chainID = pdb_file[:-4].split('/')[-1].split('_')
-            except:
-                pdbID, chainID = pdb_file[:-4], chains_inpdb[0]
-            if len(pdbID) > 4:
-                pdbID, chainID = pdb_file[:-4], chains_inpdb[0]
+            if len(chain_inpdb) > 0:
+                try:
+                    pdbID, chainID = pdb_file[:-4].split('/')[-1].split('_')
+                except:
+                    pdbID, chainID = pdb_file[:-4], chains_inpdb[0]
+                if len(pdbID) > 4:
+                    pdbID, chainID = pdb_file[:-4], chains_inpdb[0]
+            else:
+                pdb_file = 'not available'
 
             # check if this is a OPM structure
             membrane_thickness = parse_membrane_thickness_from_OMP(pdb_file)
@@ -2382,7 +2385,7 @@ def run_barros(arguments, offset = 1, step = 2, local_angle_threshold = 25, max_
                         target_chains.append([pdbID.split('_')[0], chainID, chain_pdb, protein_type, membrane_thickness])
             else:
                 target_chains = None
-        else:
+        elif pdb_file != 'not available':
             if 'AF-' not in pdbID and 'MGY' not in pdbID:
                 target_chains = [[pdbID.split('_')[0], chainID, pdb_file, protein_type, membrane_thickness]]
             else: