diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/ABoxUpdater.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/ABoxUpdater.java
index 6b4e491e8..fd56e9835 100644
--- a/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/ABoxUpdater.java
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/ABoxUpdater.java
@@ -424,9 +424,13 @@ public class ABoxUpdater {
 		OntProperty oldProperty = oldTboxModel.getOntProperty(propObj.getSourceURI());
 		OntProperty newProperty = newTboxModel.getOntProperty(propObj.getDestinationURI());
 		
-		if (oldProperty == null || newProperty == null) {
-			logger.logError(" expects non-null old property and new property "
-					+ "URIs");
+		if (oldProperty == null) {
+			logger.logError("didn't find the " + propObj.getSourceURI() + " property in the old TBox");
+			return;
+		}
+		
+		if (newProperty == null) {
+			logger.logError("didn't find the " + propObj.getDestinationURI() + " property in the new TBox");
 			return;
 		}
 		
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/OntologyUpdater.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/OntologyUpdater.java
index a2ee1d2e2..07dcc9e05 100644
--- a/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/OntologyUpdater.java
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/OntologyUpdater.java
@@ -138,7 +138,7 @@ public class OntologyUpdater {
 				} catch (Exception e) {
 					logger.logError(this.getClass().getName() + 
 							".performSparqlConstructs() unable to execute " +
-							"query at " + sparqlFile);
+							"query at " + sparqlFile + ". Error message is: " + e.getMessage());
 				}
 			} catch (FileNotFoundException fnfe) {
 				logger.logError(this.getClass().getName() +