When it first came out, I upgraded to NIS 2009 on both my desktop and notebook computers (running XP SP3 with all updates, and updates for all drivers and applications). I notice an appreciable gain in speed and overall less drain on system resources on both machines (especially after I removed Webroot Spy Sweeper from my notebook).
The desktop at home, which stays on 24/7, functions flawlessly (and practically invisibly) with NIS 2009, and thus far I’ve concluded NIS 2009 functions at its best when on a machine that is on practically all the time. Since the notebook is the one I travel with, it is not on all the time. Hence when I boot up and run Live Update, sometimes I get the error message that Virus Definitions failed to download successfully. Then when I click on “One Click Support,” it says it is installing Flash Player 10 and soon it prompts me to run Live Update Again. When I do, often it downloads a 30+ MB file (which I presume is the entire Virus Definitions file judging from size) and then prompts me to run LU yet again. That usually fixes the problem. By now I’ve gotten into the habit of just downloading and installing the 32 MB AV Definitions updater file from the onset if the computer has been off a full day or more. It seems to save a few steps through the One Click Support process. But what I’ve noticed is that the computer can be off for as little as one hour, and the definitions don’t download/install correctly and I still have to go through all the One-Click steps (or download the definitions manually). There doesn’t seem to be any consistency.
I’m going on the assumption that with daily use, the definitions updates simply append themselves to the existing definitions file. I noted in earlier versions of NIS that when it missed too many daily updates, the only way to remedy the situation was to download and install the definitions file manually. I noted a couple of days ago someone posted something similar to this. In any case, I’ve been able to work around it successfully, but thought I would bring it to the attention of Symantec for future updates/upgrades. Kelly