Event Type:     Failure Audit
Event Source:   Security
Event Category: Account Logon
Event ID:       680
Date:           02/03/2010
Time:           8:49:53 PM
User:           NT AUTHORITYSYSTEM
Computer:       RESULTANT
Description:
Logon attempt by: MICROSOFT_AUTHENTICATION_PACKAGE_V1_0
 Logon account:  NETWORK SERVICE
 Source Workstation: RESULTANT
 Error Code: 0xC0000064

Event Type:     Failure Audit
Event Source:   Security
Event Category: Logon/Logoff
Event ID:       529
Date:           02/03/2010
Time:           8:49:53 PM
User:           NT AUTHORITYSYSTEM
Computer:       RESULTANT
Description:
Logon Failure:
     Reason:        Unknown user name or bad password
     User Name:     NETWORK SERVICE
     Domain:        NT AUTHORITY
     Logon Type:    4
     Logon Process: Advapi
     Authentication Package: Negotiate
     Workstation Name:       RESULTANT

Run whether user is logged on or not

Do not store the password. The task will only have access to local computer resources

<Principals>
    <Principal id="Author">
      <UserId>S-1-5-20</UserId>
      <RunLevel>LeastPrivilege</RunLevel>
    </Principal>
  </Principals>