Index: trunk/psModules/src/concepts/pmConcepts.c
===================================================================
--- trunk/psModules/src/concepts/pmConcepts.c	(revision 12659)
+++ trunk/psModules/src/concepts/pmConcepts.c	(revision 12662)
@@ -203,4 +203,10 @@
     }
 
+    pmHDU *hdu = pmHDUGetLowest(fpa, chip, cell); // Any HDU, required for the format
+    if (!hdu) {
+        // Can't do anything --- don't record any success, but don't return an error either
+        return true;
+    }
+
     bool success = true;                // Success in reading concepts?
     if (source & PM_CONCEPT_SOURCE_CELLS && !(*read & PM_CONCEPT_SOURCE_CELLS) && cell) {