HP recommends that all computers be equipped with some type of firewall and antivirus protection. However, these programs can block all access to the network or Internet if they are not set up correctly. You should only use one antivirus or firewall program at a time. Running two or more antivirus or firewall programs at the same time can make the computer operate slowly or prevent the computer from connecting to a network or the Internet. To review and change firewall and antivirus settings, do the following:
For Windows Vista, click Start, type security in the Search field, and then select Security Center from the listing. Follow the on-screen instructions to verify the security and firewall settings are on.
For Windows XP, click Start, Control Panel, and then Security Center. Follow the on-screen instructions to verify the security and firewall settings are on.
For testing purposes only - You can temporarily disable antivirus and firewall software to determine if one of these programs is preventing access to the Internet.