XAPI Service unable to start.  It shows that the it already has a pid and is dead.

Looking at the logs xensource.log, you will find INTERNAL_ERROR as below:

• xapi top-level caught exception: INTERNAL_ERROR: [ Xmlm.Make(String)(Buffer).Error(_, -372779099) ]
  Caught exception at toplevel: 'Xmlm.Make(String)(Buffer).Error(_, -372779099)'
• This gives us an indication that XAPI is failing to start because it is unable to read the state.db correctly.
• Checking the integrity of the DB with “xmllint --format /var/xapi/state.db” returns,
  
  xmllint --format /var/xapi/state.db
  /var/xapi/state.db:1: parser error : Input is not proper UTF-8, indicate encoding !
  Bytes: 0x94 0x94 0x22 0x20 9537" __mtime="513860953" HVM__boot_params="(('order' 'dc'))" HVM__boot_policy=
• We can now tell that the DB has incorrect formatting or illegal characters.

1. Take a backup of the state.db under /var/xapi/  and remove the current state.db file as below:

2. Then do a XAPI toolstack restart as below:

3. This should bring the state.db file back in /var/xapi.  If not then the XAPI DB is corrupted, find what happened to the XAPI database.
4. After adding the XenServer to the XenCenter, introduce the local storage :

5. Create DVD drive and Removable storage as well.
6. Create default templates : /opt/xensource/libexec/create_templates.