<JOBS>
 <job ID="1" CheckForScan="True" JobName="new job (1)" Information="" PathToInputFolder="D:testinput" PathToOutputFolder="D:testoutput" PathToErrorsFolder="D:testerror" ParseSubfolders="False" UseFilter="True" Filter="*.txt" KindOfSort="Without sorting" Ascending="False" UseTemplateForTheFileName="True" TemplateForTheFileName="%ORIGNAME%.%ORIGEXT%7" UseArchiveFolder="True" PathToArchiveFolder="D:testarchive" ScanInterval="True" TimeInterval="1" ScanDate="16.08.2017 10:16:16" Daily="False" KindOfScan="" NextScan="" PreviousScan="" />
 <job ID="2" CheckForScan="True" JobName="new job (2)" Information="" PathToInputFolder="D:testinput" PathToOutputFolder="D:testoutput" PathToErrorsFolder="" ParseSubfolders="True" UseFilter="True" Filter="*.AVI" KindOfSort="Without sorting" Ascending="False" UseTemplateForTheFileName="False" TemplateForTheFileName="" UseArchiveFolder="True" PathToArchiveFolder="D:testarchive" ScanInterval="False" TimeInterval="1" ScanDate="16.08.2017 14:07:03" Daily="True" KindOfScan="" NextScan="" PreviousScan="" />
 <settings MaxThreads="5" EndPosition="0" MaxAttempts="" WaitingTime="" />
 </JOBS>

xDoc.Element("JOBS").Add(new XElement("job", new XAttribute("ID", "newOne"),..... ))