Sunday, December 30, 2007

"Medical" check-up for a computer

PC “medical” check-up

If you are known as the "PC expert" among those close to you, it may be possible that either a friend or a relative asks for your help to bring their PC back to a healthy state. For example, maybe Internet does not work properly in their laptop or just simply it takes too long to start up or to run applications.

Probably, they do not read this blog and they have not followed recommendations proposed here in the past.

Or, simply, your or their PC is not working properly. What can you do in this case then? Here you have some helpful tips:

- A full harddisk is not recommendable: Check that data occupies less than 60% of the storage capacity.

- Check that your operating system keeps on receiving automatic updates.

- Check that the antivirus is updated. Run a full scan on the hard disk. This could take a long time. After the scan, eliminate all discovered viruses and trojans.

- Check that there is an anti-malvare software installed and updated and run it. This could also take a long time. After the scan, eliminate all discovered pieces of malware (including negligible objects such as tracking cookies).

- Check that there is a personal firewall installed and running. Check the network rules defined and the application-related rules configured in the firewall. If you doubt why these rules are there, just delete them. The user would have to start again the firewall rule-creation process answering a “deny or allow” popup window any time there is an incoming or outgoing attempt to communicate. This can be tedious in the first uses but this way you get rid of undesired rules.

- Run msconfig to reduce the number of services that are run at startup time (this will decrease the bootup time considerably). Typical examples of services to disable are toolbars, instant messaging clients, printer support packages, etc.

- Open the control panel/Installed software: Uninstall everything you do not need. This will release space and complexity on the PC.

- TreeSizeFree.exe is a lightweight application that shows you the biggest files in your PC. Configure the file explorer so that you can always see all files (including the operating system files) and their extensions. Even better, use the details view mode (this way, you can see file creation date and size). Have a look at those folders with a big amount of files.

- Check your harddisk properties (In XP File explorer, right click one by one all your harddisks and check their properties e.g. size (data should occupy less than 60% space) and sharing (the harddisk should not be shared)).

- Create a user without administrative rights to browse the Internet. If you come across a zero-day exploit while browsing, this measure will limit damage.

- Check that you only have installed those network protocols required by your PC (normally only TCP7IP and nothing else).

- If there is peer-to-peer or sharing software, try to uninstall it. If you need this type of software, check which folders you are sharing with all Internet users (avoid storing personal data in the folders you share).

- From the network viewpoint, check which ports are used and open in your computer. Open a command prompt and use commands such as ipconfig -all (to see present network interfaces) nslookup (DNS information), netstat (to see open ports).

This set of tips (and a lot of imagination) could guide you in the initial phases to bring a computer back to a state ready for action. In addition, previous posts in this blog provide you with more detailed hints.

Monday, December 17, 2007

Information security sites

- Security and risk: How companies can link their information security practice with their operational risk management strategy and practice to achieve superior benefits.