Hello,
You can simply download the SP4 and using the install for upgrade. There is no particular manner recommended by SYMANTEC for upgrade. However it is recommended that the SA password should not be left blank.
Additional Information :
For information on the recent VERITAS Backup Exec security vulnerabilities, including links to the downloads for the necessary hotfixes, please refer to the following document:
Patch summary for Security Advisories VX05-001, VX05-002, VX05-003, VX05-005, VX05-006, VX05-007
http://seer.support.veritas.com/docs/277429.htm
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