I recently visited a client whose PC had literally 'ground to a halt'—it barely responded to mouse or keyboard, the 'Start' Button' and 'Taskbar' were firmly stuck at the top of the screen and most of the Windows 'Start menu' was missing.
The client suspected that this might be a 'virus' issue which was a pretty fair guess for a non-technical person.
Typically, there were no backups which might have enabled recovery in a few minutes.
In fact, the client had been very careful to protect himself against malicious software by downloading no less than 5 assorted 'internet security' products.
While it might seem logical to suppose that if one product is good then five must be better, the reality is that they all consume PC resources and will often conflict with each other.
Unfortunately, one of these 'protectors' was the notorious Antivirus XP 2008 which is actually malicious software masquerading as an internet security product—apart from infecting your machine through the offer of free scans which inevitably advise you of multiple problems, it seems that the sole object of this software is to grab your credit card details by persuading you to purchase the 'full' version.
My client suffered several unauthorised credit card debits within a day or two of his 'purchase'.
After some fiddling about, I was able to run 'Spybot', a 'respectable' malware/spyware product which was already installed on the PC—this restored enough functionality for me to uninstall all internet security products and replace them with McAFee Internet Security which provides all-round protection in one product.
The subsequent scan ran for 48 hours and identified over 5500 items of malicious/unwanted software, which is certainly a record for me.
Of course, products like McAfee can delete malicious software but cannot necessarily undo the damage that they have caused so there are a few problems yet to be resolved on this particular PC.
A few tips
- Ignore any 'pop-ups' which claim that your PC is corrupted and offer to perform a 'free' scan—it is extremely risky to allow access to unknown software and, whatever it finds, the solution is unlikely to be free
- When downloading software from 'known' suppliers, go directly to the 'known' web site address rather than responding to links on pop-ups or emails—it is very easy to produce web sites which look like those of respectable software vendors
- Before downloading software from unknown suppliers, do some 'Google' searches to see what others think of the software—also, get your 'free' or 'shareware' software from respectable download sites such as www.download.com
- Be careful not to run 'conflicting' software—for example, both Windows and McAfee Internet Security have a 'firewall' so you should run one or the other but not both, which definitely causes problems
On Windows XP, the firewall only works in the 'incoming' direction so I prefer McAfee but, with Vista, I would stick with the Windows version while still using other McAfee features
As I said at the beginning, be very careful of what you download.