Network connections failing after installation of F-Secure Internet Security 2010

In certain scenarios, after installing F-Secure Internet Security 2010 as an upgrade installation, the network may become inaccessible. This occurs if during the upgrade process the F-Secure firewall is removed and Windows Firewall is enabled and left that way after the upgrade has finished. This leaves the computer with both firewalls enabled. Using multiple firewalls on one PC might lead to interoperability and/or networking issues.

To restore network connectivity, Windows Firewall needs to be disabled.

To disable the firewall in Windows XP, do as follows:

1. Click Start and select Control Panel. The Control Panel window is displayed.
2. Double-click Security Center to open the Windows Security Center window.
3. Click the Windows Firewall link to open the Windows Firewall dialog.
4. On the General tab, select Off (not recommended) to turn off the Windows Firewall feature on all network adapters.
5. Click OK to verify the change.

To disable the firewall in Windows Vista, do as follows:

1. Click Start and select Control Panel.
2. Browse to the Security category and double-click Windows Firewall. The Windows Firewall window is displayed.
3. Click Turn Windows Firewall on or off. The Windows Firewall Settings dialog is displayed. Note: If you are prompted for an administrator password or confirmation, type the password and/or confirm.
4. On the General tab, select Off (not recommended) to turn off the Windows Firewall feature on all network adapters.
5. Click OK to verify the change.