You have a secure network thanks to your firewall - now what if you want to allow a type of network access and it is being blocked? 

First turn off the software firewall for a few moments to see if it's your firewall software that is blocking the access for that program. If the network program now works, you know to troubleshoot the firewall. If it still doesn't work, it may be your router firewall or anti-virus software. 

So let's assume your network program works with your firewall off - you need to "allow" your program in your firewall control panel. 

How you do this depends on what firewall you use, so check the manual or search for your specific firewall support on the Internet. 

You probably also have a firewall on your router, where your Internet passes from the "public" Internet to your "private" Internet. Some firewalls need to be adjusted on the router, also. 

Follow the same process: Disable the firewall and see if that allows the service to run. Configuring router firewalls may involve "port forwarding" and will be covered in another article. 

Anti-virus programs are really important on Windows and should always be enabled. A firewall doesn't stop you from installing or copying files and software that may be dangerous. 

Maybe you accidentally click on a Web page that wants to install malicious software. Without anti-virus protection you may never find out that a program has installed itself and is copying your private information. 

Anti-virus software will scan every file as it arrives on your computer by way of the Internet or if you copy it from somewhere like a USB drive. 

The anti-virus software has a library of known malicious software to look for, and if it finds something it thinks is unsafe it will put it in a "vault" where it can't do any damage and either delete it automatically or let you know. 

Anti-virus software can cause problems when you are installing software you trust and your anti-virus software decides to be overprotective. If you install trusted software and you find it doesn't work, check your anti-virus software to see if it has vaulted your software. 

You can then choose to tell your anti-virus software that you do trust it, and it should remember this for you and not remove it again. 

Software manufacturers can also take steps to ensure that their software is trusted by digital signing, so discuss this with them also. 

Some anti-virus software is very strict and just won't let you use the software you want to use. In this case you can choose to install another kind of anti-virus software, or discuss your options with your anti-virus support team. 

Why don't firewalls block viruses? 

Firewalls can't stop malicious code from getting into your system because you also need your computer to download software and files that you may trust and have been compromised, or copied an affected USB drive, for example. 

Once the malicious code is on your computer it can run an "exploit," where good software has a bug that can be used to trick your system into running the malicious code. 

You probably run your computer as an "admin" user. This means that you have permission to make file and system changes.

So if you accidentally get a virus installed on your computer, it has the same permissions as you do and it can trick your system into running it like a program you have authorized. 

You don't want to use your computer without downloading files, reading your email or using browser plug-ins like Flash and Java, so it's critical that you have an anti-virus program installed that regularly updates its library of known "exploits." 

Windows is working to make itself more secure – since in Windows Vista there is now user account control so you are notified if something new wants to run.

However, many people turn this off because it disrupts you from actually using the computer, and after many alerts during the day you may stop reading the messages and just automatically, or accidentally, click "OK." 

The built-in firewall that comes with Windows is a good option. It provides flexibility and it's easy to test with. 

If you prefer another option, you should choose a firewall that allows fine-grained control over which type of traffic is allowed or not allowed, and one that can allow certain applications. It's a good idea at first to enable alerts so you are notified when an application is trying to use the Internet. 

Windows doesn't come with a built-in anti-virus option, so find something that works for you and your budget. Some providers offer a combined firewall and anti-virus, which can make it easier to manage blocked services. 

MAKING IT ALL WORK 

You may find it takes some patience and troubleshooting to find out what settings work for you. 

Take the steps of disabling all firewalls and anti-virus and slowly turn them on one-by-one. This helps you understand which software is blocking your network program. 

It's almost impossible to troubleshoot network problems with everything turned on, so take the time to understand what firewall and anti-virus software you are running. 

Lastly, don't forget to turn them back on after you are done troubleshooting. 

SO AM I SAFE? 

The world of viruses and exploits is changing every day. No one, even on Mac OSX, is completely safe from having private data be subjected to manipulation if their computer is network enabled. 

You can stay safe by making sure your firewall and anti-virus is on and regularly updated. Turn on auto-update if you can, and use an anti-virus service that updates its library of known exploits daily. 

If you have extremely sensitive data, don't keep it on your computer in readable form. 

Using good quality disk encryption like PGP or TrueCrypt is the only safe method because even connecting an external drive or USB drive can be compromised by an affected computer.  

Mac OSX currently doesn't have a firewall enabled by default. You will probably only encounter a firewall on your router, and we'll discuss router firewalls in the next article. 

Mac users will know that installing software requires entering your system password. This keeps you safe for the most part. 

The Mac has traditionally been safe from viruses, largely due to the fact that it has fewer people using it and, as a Unix variant, it has peer-tested security. 

Apple is becoming more popular however, so the company has taken steps since OSX 10.7.5 to encourage the practice of only allowing the installation of digitally signed software. 

This means that the manufacturer has verified with a trusted party that they are who they say they are, and it helps Apple block malicious attempts from happening at all. 

Mac OSX also has a built-in encryption method called FileVault. If you store sensitive data, make sure to enable this when possible.

ABOUT REBEKAH
Rebekah Wilson is the technical director and one of the co-founders of Source Elements, which created and markets Source-Connect software for remote audio recording and real-time collaboration. Her main goal in life is to keep improving network collaboration software so she can continue to travel. She's lived in over 10 countries and loves that she gets to ask (and gets asked) "where are in the world are you?" every day. 

Email: rebekah@source-elements.com
Web: www.source-elements.com