2019-01-03 09:07:41.268: Running.
2019-01-03 09:07:41.378: Fetching build definition.
2019-01-03 09:07:41.997: Fetched build definition. 'Dynamicweb.Security.UserManagement.Indexing.UserIndexBuilder'.
2019-01-03 09:07:42.059: Preparing schema.
2019-01-03 09:07:42.106: Prepared schema.
2019-01-03 09:07:42.154: Creating index writer.
2019-01-03 09:07:42.203: Created index writer: 'Dynamicweb.Indexing.Lucene.LuceneIndexWriter'.
2019-01-03 09:07:42.235: Starting build process.
2019-01-03 09:07:42.297: Dynamicweb.Security.UserManagement.Indexing.UserIndexBuilder building using Dynamicweb.Indexing.Lucene.LuceneIndexWriter... Action: 'Full', Resume: 'False'
2019-01-03 09:07:42.344: Opening index writer.
2019-01-03 09:07:42.406: Users index builder experienced a fatal error.. System.IO.IOException: The process cannot access the file 'D:\home\site\wwwroot\Files\System\Indexes\Content repository\Installers index\Installers B\write.lock' because it is being used by another process.    at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)    at System.IO.File.InternalDelete(String path, Boolean checkHost)    at Lucene.Net.Store.NativeFSLockFactory.ClearLock(String lockName) in d:\Lucene.Net\FullRepo\trunk\src\core\Store\NativeFSLockFactory.cs:line 124    at Lucene.Net.Store.Directory.ClearLock(String name) in d:\Lucene.Net\FullRepo\trunk\src\core\Store\Directory.cs:line 120    at Lucene.Net.Index.IndexWriter.Init(Directory d, Analyzer a, Boolean create, IndexDeletionPolicy deletionPolicy, Int32 maxFieldLength, IndexingChain indexingChain, IndexCommit commit) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\IndexWriter.cs:line 1227    at Lucene.Net.Index.IndexWriter..ctor(Directory d, Analyzer a, Boolean create, MaxFieldLength mfl) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\IndexWriter.cs:line 1019    at Dynamicweb.Indexing.Lucene.LuceneIndexWriter.Open(Boolean openForAppend)    at Dynamicweb.Security.UserManagement.Indexing.UserIndexBuilder.Build(IIndexWriter writer, Tracker tracker)
2019-01-03 09:07:42.406: Users index builder experienced a fatal error.
2019-01-03 09:07:42.610: Failed.
2019-01-03 09:07:42.656: Closing index writer.
2019-01-03 09:07:42.719: BuildIndex failed.. System.NullReferenceException: Object reference not set to an instance of an object.    at Dynamicweb.Indexing.Lucene.LuceneIndexWriter.Close()    at Dynamicweb.Indexing.Index.Build(String instance, String name, Tracker tracker)    at Dynamicweb.Indexing.IndexService.<>c__DisplayClass14_0.<BuildIndex>b__0(Tracker tracker)
2019-01-03 09:07:42.719: BuildIndex failed.