altiris client service is stop and not be able to start it?
What the error reflect while start it?
Do you have received any error ?
Try to repair add/remove program
message is Error code 1067 - the process terminate unexpectly.
Not tried to repair it. But will try it and update.
Is this work for you?
Edit
Alternate solution is attach in below thread
https://www-secure.symantec.com/connect/forums/altiris-service-error
Error, "Could not start the Altiris Agent service on Local Computer. Error 1067: The Process Terminated Unexpectedly"
http://www.symantec.com/business/support/index?page=content&id=TECH36456