I think this KB is more useful:
"How to change the password of the Application Identity account"
Solution
1. Create a separate account that is a Symantec Administrator to the SMP and has DBO access to the Symantec_cmdb database.
2. Reconfigure the application identity on the console under Settings – All Settings –Notification Server – Notification Server Settings with this separate account.
3. Verify that the Altiris services are now configured to use the new account.
4. Once the settings have been changed, restart IIS. IIS may have cached the old credentials.
5. Take note in the console such as replication credentials or other process that may be using the application identity account as a “specified account” where the account information is entered manually. These locations will also need to be changed to the separate account or changed if possible to use the “Use Application Identity” setting.
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http://www.symantec.com/docs/TECH194254