diff --git a/pyne/origen22.py b/pyne/origen22.py
index b4df375f3a..e0f8ef95be 100644
--- a/pyne/origen22.py
+++ b/pyne/origen22.py
@@ -1509,15 +1509,28 @@ def xslibs(nucs=NUCS, xscache=None, nlb=(201, 202, 203), verbose=False):
         t9[nlb[2]][field] = {}
     # fill with data
     for nuc in nucs:
-        if verbose:
-            print('computing {0}'.format(nucname.name(nuc)))
-        key = nucname.zzaaam(nuc)
-        if nuc in ACTIVATION_PRODUCT_NUCS:
-            _compute_xslib(nuc, key, t9[nlb[0]], xscache)
-        if nuc in ACTINIDE_AND_DAUGHTER_NUCS:
-            _compute_xslib(nuc, key, t9[nlb[1]], xscache)
-        if nuc in FISSION_PRODUCT_NUCS:
-            _compute_xslib(nuc, key, t9[nlb[2]], xscache)
+        try:
+            if verbose:
+                print('computing {0}'.format(nucname.name(nuc)))
+            key = nucname.zzaaam(nuc)
+            if nuc in ACTIVATION_PRODUCT_NUCS:
+                _compute_xslib(nuc, key, t9[nlb[0]], xscache)
+            if nuc in ACTINIDE_AND_DAUGHTER_NUCS:
+                _compute_xslib(nuc, key, t9[nlb[1]], xscache)
+            if nuc in FISSION_PRODUCT_NUCS:
+                _compute_xslib(nuc, key, t9[nlb[2]], xscache)
+        except KeyError:
+            print('Key Error with ', key, ' in a computing cross sections')
+            continue 
+        #if verbose:
+        #    print('computing {0}'.format(nucname.name(nuc)))
+        #key = nucname.zzaaam(nuc)
+        #if nuc in ACTIVATION_PRODUCT_NUCS:
+        #    _compute_xslib(nuc, key, t9[nlb[0]], xscache)
+        #if nuc in ACTINIDE_AND_DAUGHTER_NUCS:
+        #    _compute_xslib(nuc, key, t9[nlb[1]], xscache)
+        #if nuc in FISSION_PRODUCT_NUCS:
+        #    _compute_xslib(nuc, key, t9[nlb[2]], xscache)
     xscache['E_g'] = old_group_struct
     xscache['phi_g'] = old_flux
     return t9
diff --git a/pyne/xs/cache.py b/pyne/xs/cache.py
index 8748aecc64..c1e54ded42 100644
--- a/pyne/xs/cache.py
+++ b/pyne/xs/cache.py
@@ -114,9 +114,9 @@ def __getitem__(self, key):
                     xsdata = ds.discretize(**kw)
                     if xsdata is not None:
                         self._cache[key] = xsdata
-                        break
-                    else:
-                        self._cache[key] = [0]           
+                        break        
+                else:
+                    raise KeyError
         # Return the value requested
         return self._cache[key]
 
@@ -131,8 +131,8 @@ def __setitem__(self, key, value):
                 return
             self.clear()
             self._cache['phi_g'] = None
-            #for ds in self.data_sources:
-            #   ds.dst_group_struct = value
+            for ds in self.data_sources:
+               ds.dst_group_struct = value
         elif (key == 'phi_g'):
             value = value if value is None else np.asarray(value, dtype='f8')
             cache_value = self._cache['phi_g']