Rob Freeman, Click Online's very own Mr Fixit, troubleshoots your PC problems.
Remember the last time that you heard about crackers getting into someone's computer and using it to send out viruses, or spam, or spyware? Did you think: "I hope that doesn't happen to me?"
Good. But did you do anything about it?
Asia Nayaab Rais contacted us to ask:
I have been using the internet for quite a while now but I still don't know what the word firewall means exactly. People say that you cannot access our services because you are behind a firewall but they also say a firewall protects your system. Is it good or bad?
Undeniably firewalls are a good thing.
Simply put, they are a protection barrier between you and someone who might want to get into your computer. A bit like a bouncer at a nightclub.
However, they can become very frustrating if they are not set up properly or are not under your control.
The same is true of the bouncer - if they are letting in the wrong people and blocking the right - no one is happy.
So, once installed, a firewall, while stopping unknowns from getting in to your computer, can also stop you from accessing places you are used to visiting.
And with an accidental click of the mouse you can give the baddies access.
Derek Heathcote from Newark in the UK e-mailed us to say:
I have installed SP2 and also use Norton firewall but have been advised by various experts that it is not a good idea to have both as they are said to clash. What is your advice?
There was an early issue with Norton being used with Service Pack 2, although Symantec, which makes Norton, says it has been fixed, so you can use them at the same time if you wish.
But it is likely to be a download, so make sure you keep both Windows and your firewall software up to date.
However, people are probably advising you only to use one of them not for anything to do with security, but to stop your stress levels shooting through the roof as you continually make alterations to the settings on both of them in order to get your computer to work properly.
Microsoft's firewall is free and simple, but if you have already got another product you think is better, you can use that instead, and turn the Windows one off.
You will find an icon for the Windows firewall in your control panel. The rest is self explanatory.
You can also buy a firewall as a separate device, and hardware firewalls have previously been used for corporate internet security and thus are expensive and certainly more difficult to setup, but prices have now fallen dramatically.
Many believe hardware to be superior solution. But is this still the case?
Software has seen measurable improvement over the last four or five years.
I would be interested in hearing from you if you have an opinion on whether hardware firewalls are still worth the money and the effort.
Part of the answer comes from Richard Hesketh, here in Britain, who watched a few weeks ago when we looked at the differences between USB and Ethernet modems.
He points out one big plus with a modem which has Ethernet sockets:
Ethernet modems for broadband lines can come with a built-in firewall, and can protect all the computers using that connection.
A decent software firewall usually costs extra and could be turned off by some viruses. They cost slightly more than a USB modem but they save you the cost of the software version and when combined with anti-virus software on the PC gives you 'defence in depth'.
Of course Windows PC users fed up with viruses, spyware and endless crashing could also move over to Linux or better still buy an Apple Mac!
Key tip - firewalls do not scan and remove viruses - although they can prevent some from entering.
Firewalls cannot protect you against spyware and other nasties you might get from the web, or sent to you via e-mail. A firewall is just one part of online safety.
If you have got Windows XP you have got a firewall. Just make sure it is on. Also, you could also try the popular freebie ZoneAlarm.
A few weeks ago, it was noted that I claimed it was not possible to change an NTFS disk back into a FAT partition.
I do not know what I was thinking that day.
Actually, I do know what I was thinking - I was thinking wrong!
What inspired my comment was that, to the best of my knowledge, Windows does not allow you to convert, but Paul Cox from Bude in Cornwall pointed out:
There are many applications available to do this, but perhaps the most widely used is Partition Magic.
This bit of software is now onto version eight, and has recently been bought by Symantec.
Its big thing is that it will let you change and resize partitions without losing any data.
It does have its competitors; one is Paragon Partition Manager, and another is the Disk Director Suite, which does exactly what the other two do by the looks of things.
So thanks for pulling me up there Paul - and everyone else who mailed to point out my mistake!
If you are broke and do not want to buy any of those third party applications, you can always reformat the disk again in any format you choose, but that means re-installing everything afterwards.
And do not forget to back up.
If you have any questions or queries, please visit "Contact us" (link on the top right-hand side of this page) to get in touch.
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