The general rule is;
1] Only one Firewall. If you have an anti-virus/firewall combination application, ensure only one firewall.
2] Only one anti-virus. Two or more, both running background scans, can cause conflict as they fight to scan the same data at the same time.
3] Any number of anti-malware scanners, (such as MBAM or SAS), but none of them should be set to scan in the background, and should just be used as occasional, (once a week or so), manual scanners.
Mark
I'm going for my A+ Cerification and know alot of guys in the IT field. Long and short of it, was that one of my friends CP's kept dumping/crashing and it always said, at the end of the errror message: SDVRAAM problem. I talked to a close friend who suggestested testing the RAM sticks one at a time and thereby, through the process of elimination, determine which paticular stick was bad. Needless to say, I follwed his instructions to the letter and the end result was that none of the sticks were bad; but I did get it too finally boot up in Safe Mode (Win7 Home Premium), and immediatly went to uninstall. As soon as I seen Norton near the top I put two n two together, uninstalled Norton ASAP and he hasn't had a problem since. I, on the other hand, envisioning these two virus programs battling for control of the computer inside it, to the point that they were both willing to destroy my friends computer, rahter than one give way to the other; or, in my opinion best of all, walk side by side and act as double duty protection of their host, Such is not the cae, just in case you happen to run in a similar difficulty with similar programs conflicking and causing serious functional problems for the PC owner.

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