A change was made to the Symantec Installation Manager to make sure all installs and repairs are done using the Altiris Service ID, known as the AppID or SMP Application Identity.
This is part of the fixes and changes done in ITMS 7.6 HF4. Please refer to Release Notes (DOC8949):
Under Page 8:
Note: To upgrade to the lastest hotfix, log on to Notification Server with the SMP application identity credentials.
As well it is mentioned under the Fixed issues for Symantec Installation Manager (Table 1-9)
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