Ok. new error on that one:
System.Data.SqlClient.SqlException: The DELETE statement conflicted with the REFERENCE constraint "FK_Forum_Threads_Forum_Posts". The conflict occurred in database "C8913_dnn", table "dbo.Forum_Threads", column 'LastPostedPostID'. The statement has been terminated. at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection) at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) at System.Data.SqlClient.SqlCommand.RunExecuteNonQueryTds(String methodName, Boolean async) at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, Boolean sendToPipe) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at DotNetNuke.Data.SqlDataProvider.ExecuteADOScript(String SQL) at DotNetNuke.Data.SqlDataProvider.ExecuteScript(String Script, Boolean UseTransactions) Delete From dbo.Forum_Posts where PostID = 365