Created Unassigned: null ref ex when store all to DB [3153]

2015-02-25 14:08:45,041 [4] ERROR ResourceManager.Client.MainForm [(null)] - Error while processing task.
System.AggregateException: One or more errors occurred. ---> System.NullReferenceException: Object reference not set to an instance of an object.
at ResourceManager.Storage.TranslationStorageManager.<>c__DisplayClass14.<Store>b__8(KeyValuePair`2 data)
at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
at System.Linq.Enumerable.Count[TSource](IEnumerable`1 source)
at ResourceManager.Storage.TranslationStorageManager.Store(VSSolution solution)
at ResourceManager.Client.MainForm.storeAllTranslations()
at System.Threading.Tasks.Task.Execute()
--- End of inner exception stack trace ---
---> (Inner Exception #0) System.NullReferenceException: Object reference not set to an instance of an object.
at ResourceManager.Storage.TranslationStorageManager.<>c__DisplayClass14.<Store>b__8(KeyValuePair`2 data)
at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
at System.Linq.Enumerable.Count[TSource](IEnumerable`1 source)
at ResourceManager.Storage.TranslationStorageManager.Store(VSSolution solution)
at ResourceManager.Client.MainForm.storeAllTranslations()
at System.Threading.Tasks.Task.Execute()<---