diff --git a/ProvinceMapper/Changelog.txt b/ProvinceMapper/Changelog.txt
index f8fae95ee..3c1029f0a 100644
--- a/ProvinceMapper/Changelog.txt
+++ b/ProvinceMapper/Changelog.txt
@@ -1,5 +1,9 @@
 ProvinceMapper Change Log
 
+0.9D
+- Make map inversion optional (CK2 doesn't need it)
+- Throw a more useful error when a province is mapped but doesn't exist in game data
+
 0.9C
 - Optionally read province names from localization instead of map data
 
diff --git a/ProvinceMapper/Mapping.cs b/ProvinceMapper/Mapping.cs
index dd809b955..b5094d824 100644
--- a/ProvinceMapper/Mapping.cs
+++ b/ProvinceMapper/Mapping.cs
@@ -60,6 +60,8 @@ public ProvinceMapping(string line, string srcTag, string destTag, List<Province
                                     {
                                         return p.ID == provID;
                                     });
+                                if (prov == null)
+                                    throw new Exception(String.Format("Province \"{0}\" appears in a mapping, but not in game data!", prov.ToString()));
                                 if (prov.mapping != null)
                                     throw new Exception(String.Format("Province \"{0}\" appears in more than one mapping!", prov.ToString()));
                                 prov.mapping = this;
@@ -74,6 +76,8 @@ public ProvinceMapping(string line, string srcTag, string destTag, List<Province
                                     {
                                         return p.ID == provID;
                                     });
+                                if (prov == null)
+                                    throw new Exception(String.Format("Province \"{0}\" appears in a mapping, but not in game data!", prov.ToString()));
                                 if (prov.mapping != null)
                                     throw new Exception(String.Format("Province \"{0}\" appears in more than one mapping!", prov.ToString()));
                                 prov.mapping = this;
diff --git a/ProvinceMapper/MappingReader.cs b/ProvinceMapper/MappingReader.cs
index aed539dce..3448cff58 100644
--- a/ProvinceMapper/MappingReader.cs
+++ b/ProvinceMapper/MappingReader.cs
@@ -36,11 +36,25 @@ public MappingReader(string _path, string _srcTag, string _destTag, List<Provinc
                 {
                     if (line.StartsWith("link"))
                     {
-                        mappings.Add(new ProvinceMapping(line, srcTag, destTag, srcProvs, destProvs));
+                        try
+                        {
+                            mappings.Add(new ProvinceMapping(line, srcTag, destTag, srcProvs, destProvs));
+                        }
+                        catch (Exception e)
+                        {
+                            System.Windows.Forms.MessageBox.Show(e.Message, "Error in mapping file");
+                        }
                     }
                     else if (line.StartsWith("#"))
                     {
-                        mappings.Add(new CommentMapping(line));
+                        try
+                        {
+                            mappings.Add(new CommentMapping(line));
+                        }
+                        catch (Exception e)
+                        {
+                            System.Windows.Forms.MessageBox.Show(e.Message, "Error in mapping file");
+                        }
                     }
                     else if (line.StartsWith("mappings") || line.StartsWith("{") || line.StartsWith("}"))
                     {