Not very useful error reporting.  Basically for me, it was a case of it rolling back right after "preparing virus definitions" or something of that nature.

Symantec has a KB article called "How to create a detailed installation log for Symantec AntiVirus Corporate Edition 8.0".  I can't paste the link 'cause it's sooo looong.  Goto http://www.symantec.com/techsupp/enterprise/products/sav/sav_8_ce/index.html and click "Knowledge Base" and then enter the search "install log"
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