True to tradition, McAfee have announced (late) that one of their updates is blocking internet access. I've seen a few of these this week and I've fixed them all by removing / reinstalling the program, but theres a workround at
http://service.mcafee.com/faq/TS101446.htm

Symptoms are that it blocks internet access by seemingly messing up DNS resolution. It even prevents logging into the router, even though the physical connection is working. With Sky routers it also seems to somehow spike them into not responding - you may also need to reset them to defaults to regain access.

Thankfully not a McAfee user. But I do program industrial control systems, and we have to test any software modifications to buggery before they are allowed anywhere near their target systems. Then we have to prove, by various means, th correct update and nothing else has been installed.

Do these software suppliers actually have any testing regimes?

Blues&twos,

Do these software suppliers actually have any testing regimes?

Like most things in the IT industry, you get what you pay for.

If you pay peanuts you're looking at a volume sales driven product, so the company's focus is on a quick route to market and getting the sales volumes up. Same goes for Open Source software where the quality and depth of QA varies vastly, even more widely than what you see between commercial companies !

Pay more, you (generally) get a more robust product, backed by a more robust development programme and a more conservative software release policy.

That said, its not all the AV vendor's (or other software types) fault... there are so many possible use-cases, due to a large number of deployment scenarios and end-user platform configurations, that there will always be a number of elements that they can't test and have to fix reactivley rather than proactivley.

Ok, makes sense, particularly the"you get what you pay for" which seems to apply almost universally to anything on which you can spend your readies.