Because new threats appear every day, BitDefender antivirus must be updated periodically. The updates can be of these types:
· Virus signatures: databases of Virus prints to be compared with the scanned files. Shown as Virus Definitions Update. These updates require restarting BitDefender. The restart occurs automatically.
· Spam signatures: rules for the heuristic and URL filters increasing the effectiveness of the antispam engine. Shown as AntiSpam Update.
· Product upgrades: new product features, scan techniques and hotfixes. Shown as Product Update. Occasionally, installing these updates requires restarting the computer.

To configure the automatic Update do the following:
· Open BitDefender and click Update.
· Click Settings.
· Configure the Update location settings.
BitDefender 9 includes two Update locations, allowing one of them to point to a local mirror.
· Configure the Automatic Update options.
Select Automatic check for updates to find out when updates are available.
BitDefender checks for updates every 1 hour. Click Verify every hours to modify the number of hours after which a check for updates is performed.
Leave the Confirm Update to Silent Update unless you desire to be prompted before downloading the updates or before installing them. A similar option is available for the manual Update under the Manual Update settings.
· Configure the Advanced options.
To prevent prompts asking for reboot, select Wait for reboot, instead of prompting.
· Click Apply to save the settings.
· Click Default to restore the default settings.

Occasional updates can be perfomed at any time, even when the product is set to Update automaticaly:
· Open BitDefender and click Update.
Click also Update at the top of the window if the Settings are displayed.
· Click Update now to start the Update process.
If the option Prompt before downloading updates was selected in the Settings, and when updates are available, a list of the updates available for download is displayed. Select the product to install and click Details to see the file download details. Select Switch to silent Update (don't ask me again) to stop being prompted on manual Update. Click OK to download and install the new files or Cancel to postpone the Update.