Computers & Computer Viruses - a dead simple guide
|Computers & Computer Viruses - a dead simple guide by Arf Arf Hoaxhound
What is a computer virus?
Nothing more than a simple but devious programme, which is spread by attachments in e-mails, e-mails, and the internet, most commonly in that order.
What do they do?
Varies. From mildly irritating to worldwide chaos. Often almost as irritating are hoaxes, which are e-mails about viruses that don’t exist – i.e. hoaxes.
What should I do?
Prevention is immeasurably better – and easier - than a cure
Stand Alone User
If you are a stand-alone user (i.e. you, a computer and a phone-line) you have to have good anti-virus software installed, AND REGULARLY UPDATED. There are about half-a-dozen propriety companies all offering much the same service. Do a www.google.com search on “anti-virus software” and take your pick. Lit-Net Ed has recently switched from NAI to Norton’s Symantec 2003, which is geared for stand-alone users – default is to automatically update the installation whenever you go on-line. You can expect to pay between £20-£30 for the programme and 12 months on-line updates. It’s far better to install from a cd than on-line, and make the emergency floppy disc set as instructed. Windows-based PCs are most vulnerable, then Macs, then Linux systems, but you should install AND update good anti-virus software. Otherwise it’s like driving nose-to-tail on the Information Highway in a complete MOT failure. Sooner or later you’ll crash, maybe taking other wrecks with you.
Networks are at least two machines linked together where all stuff from the internet should go through effectively just one entry point. (In information highway terms, a network is a housing estate where all roads are cul-de-sacs apart from one to enter or leave this part of suburbia.) Usually you should be okay, especially if you are part of a largish network (eg local authority, university, medium to large business) with an IT department and a network manager. You can often tell you’re okay by the message at the foot of your e-mail which says “….Mailsweeper….” or the like.
You might not be okay in a small network without an IT department or manager – typically half-a-dozen to a dozen machines(although the public sector - nhs, councils - can range from being paranoid to haphazard, sometimes both.) It’s less likely you’ll be without anti-virus protection than it not being updated and upgraded (for example, no one renews the annual subscription and no one knows until a virus hits.) If the network is a mess with several ways in and out from the housing estate to the internet, then you’re at risk wherever those access points haven’t full up-to-date cover. Similarly even if your network is bang up-to-date, it doesn’t entail a lap-top you borrow from the office is covered – stand alone rules apply.
What else can I do to prevent being infected?
You should be okay if you have good updated anti-virus software. You should delete UNOPENED all junk mail. You should not open any attachment you’re not sure about – if it looks at all iffy, e-mail the sender back to check – assuming you want to open it in the first place. Beware especially of ‘come-ons’… “Click on the attachment to know someone loves you…” This is how the Melissa virus spread so fast. If possible, be off-line (ie not on the internet) before opening any e-mail. This will prevent any virus spreading. You should virus scan any floppy disc anyone gives you – good anti-virus programmes should do this automatically. Finally keep your ears open for broadcast announcements on tv or radio about new viruses. These are almost always reliable. Note the virus name, and check on your anti-virus software website for details to be wary of.
Suppose I receive a virus warning. What should I do?
Nothing at first. Just think about it for a while.
There are two sorts of warning.
ANTI-VIRUS SOFTWARE GENERATED. This comes from inside your machine triggered by a virus being detected by your anti-virus software. Usually a note which comes up on screen “Virus xyz detected in uvw document. Suggested options….” Follow their suggestions and clean it out. You may e-mail the sender to tell them politely they’ve sent you a virus, or someone using their address (the Klez viruses send e-mails pretending they’ve been sent from someone else in the sender’s address book.) Please don’t lose your temper, but give the name of the virus and the web address of your anti-virus software so they can do something about it.
E-MAIL GENERATED. This has to come from someone else. It’s either a genuine warning or a hoax. To sort this out, go to your anti-virus software website, then its library and/or search by the name of the virus. This will tell you if it is a hoax or not.
By and large e-mail hoax alerts outnumber bona-fide alerts by at least ten to one.
You can usually reckon that anything which says it will wipe your C-drive clean or the floor with your dead maiden-aunt at three-card draw is a hoax. Some may look more convincing (the jdbgmgr.exe is hoax but refers to a real file somewhere in the sash-box of Windows) but if you check on your anti-virus software website then you know. Far better to know and not look a naïve charlie by spreading a hoax warning when one of your recipients e-mails you back to tell you so. Equally if you receive something you know is a hoax, feel free to e-mail back the sender to politely explain just that. Best just to the sender rather than any great long address lists they may've sent because they or someone else may have already done this. (Let them sort it out.)
Be on red alert. Check you anti-virus software site for latest news and update your installation. Do a full system scan (you can leave the machine alone during this) to ease your mind. If it’s a warning that’s been e-mailed by a network saying you have sent a virus to them then you probably are infected….
What do I do if my machine is infected?
You can often tell if your machine behaves oddly. (Slow to respond, plenty of crashes, oddities on the screen……) Also many networks will generate an e-mail reply stating they detected a virus in an e-mail from you. Take these very seriously, especially if you get at least two from differing sources. (Sometimes the mailsweeper settings are set so high – hello, Shropshire County Council - an unusual character may trip the system.) By all means phone the network manager to ascertain the nature of the virus.
If you’ve the tiniest suspicion your machine is infected DO NOT send any more e-mails until you’ve demonstrated your machine is clean.
Next. Attempt a full system scan with updated anti-virus software, and act appropriately.
If a virus has already crashed your machine, and it won’t come back up, boot-up using the rescue disc set the anti-virus software asked you to create and keep in a safe place when you installed it. (Which you did of course, didn’t you?)
If this fails or you don’t understand what ‘boot-up using….’ find someone with technical knowledge to help.
If you have a virus and don’t have any or out-of-date anti-virus software, this can be a very difficult and time-consuming process. Many viruses cannot be removed easily if they’re there before the anti-virus software. It may eventually mean wiping your hard-drive clean, which may mean relying on backed-up data (YOU DO BACK UP, DON’T YOU? INCLUDING CONTACT LISTS, ADDRESS BOOKS, AND WILL THE BACK UP WORK….?) and the humungious fag of reinstalling all that software (YOU DO KNOW WHERE ALL THOSE CD-S ARE, AND IT TAKING TWO HOURS TO DO IN THE FIRST PLACE.)
Once your machine is free of viruses, by all means e-mail people to tell them you’re back on-line, free from bugs, apologise for any inconvenience and could they send all those e-mails, documents, and contact details you’ve unfortunately lost. Believe you me, spreading a computer virus does nothing for you or your organisation’s street cred on the information highway.
Make sure you’ve fitted and updated your anti-virus software NOW.
|© 2001; Arf Arf Hoaxhound