Actually, it shouldn't be the Altris Client Service. That's a backup/management suite, intended to remotely manage your computer, by doing things like installing software updates, etc. On the other hand, this sounds very similar to a type of rootkit that appears to be regaining popularity again. This rootkit wi8ll literally cut off internet access through the .dll files used by IE, which cuts off most web browsers. (However, a few still work, because they use custom connection management tools. Which ones, I can't remember off the top of my head.) The best ways to check for a rootkit are strewn all over the internet, so if you have a second computer, I recommend searching around for rootkit removal tips. (Please note that final removal almost always requires going into the system files and manually deleting the rootkit, since they delete themselves from the windows file index, effectively hiding themselves from most software)
Also, thinking more on the issue, why do you have a computer with the Altris Client Service installed? That's something intended to be used in a large corporate environment, where there are a lot of computers to manage and too few people to manage them all directly. It sounds like you got the computer recently, and the service it still trying to connect to the corporate server, which would have been an on-site server probably blocked from the outside. The service wouldn't be your problem, for sure, but it indicates that your probably got this computer secondhand, and that there could be all sorts of nasty surprises waiting for you on it. Especially since the hard drive obviously wasn't wiped first. The best thing to do, in this case, is simply get an OS install disc, wipe the hard drive, and install a clean copy of the OS. That should not only solve the problem for you, it would also be doing a favor for whatever company has potentially private data left on that hard drive.
