diff --git a/src/org/fdroid/fdroid/data/AppProvider.java b/src/org/fdroid/fdroid/data/AppProvider.java
index d3db88326..c931fa2bd 100644
--- a/src/org/fdroid/fdroid/data/AppProvider.java
+++ b/src/org/fdroid/fdroid/data/AppProvider.java
@@ -66,8 +66,11 @@ public class AppProvider extends FDroidProvider {
             if (cursor != null) {
                 cursor.moveToFirst();
                 while (!cursor.isAfterLast()) {
-                    for( String s : Utils.CommaSeparatedList.make(cursor.getString(0))) {
-                        categorySet.add(s);
+                    String categoriesString = cursor.getString(0);
+                    if (categoriesString != null) {
+                        for( String s : Utils.CommaSeparatedList.make(categoriesString)) {
+                            categorySet.add(s);
+                        }
                     }
                     cursor.moveToNext();
                 }
diff --git a/src/org/fdroid/fdroid/views/fragments/RepoListFragment.java b/src/org/fdroid/fdroid/views/fragments/RepoListFragment.java
index a1ef3e9fd..d07e2fa00 100644
--- a/src/org/fdroid/fdroid/views/fragments/RepoListFragment.java
+++ b/src/org/fdroid/fdroid/views/fragments/RepoListFragment.java
@@ -407,7 +407,9 @@ public class RepoListFragment extends ListFragment
     private void createNewRepo(String address, String fingerprint) {
         ContentValues values = new ContentValues(2);
         values.put(RepoProvider.DataColumns.ADDRESS, address);
-        values.put(RepoProvider.DataColumns.FINGERPRINT, fingerprint.toUpperCase(Locale.ENGLISH));
+        if (fingerprint != null && fingerprint.length() > 0) {
+            values.put(RepoProvider.DataColumns.FINGERPRINT, fingerprint.toUpperCase(Locale.ENGLISH));
+        }
         RepoProvider.Helper.insert(getActivity(), values);
         finishedAddingRepo();
     }