When you get the paid version of Bitdefender's Antivirus Plus, Internet Security or Total Security application, you can select between one to 10 licenses for the product, which means you can install Bitdefender normally on another computer if you have additional license slots remaining. If you have already used up your available license slots, however, uninstall Bitdefender from at least one computer before you can install it on your new machine.
Uninstall Bitdefender from your old computer. On Windows 8/8.1, press "Windows-X" to open the Power User menu, and then select "Programs and Features." On Windows 7, type "Programs and Features" (without quotes) into the Start menu, and then press "Enter." Select your Bitdefender product from the list of applications, and then click "Uninstall." On the Bitdefender Uninstall Wizard, click "Remove," and then click "I Want to Permanently Remove It." Once removed, restart your computer to let the changes take effect.
Go to the Bitdefender Uninstall Tool download page. Click the "Uninstall" button under your Bitdefender product, and then double-click the Uninstall Tool after downloading it to your computer. Click the "Uninstall" button, and then wait for the Uninstall Tool to remove all traces of your Bitdefender installation, including your registration information.
Visit the Bitdefender downloads page from your new computer to download the installer for your Bitdefender product. After downloading, double-click the installer file, and then click "Install" to begin installation. If you have an installation disc for your Bitdefender product, insert it, and then select the "Install" option from the AuroRun screen.
Enter your Bitdefender license key on the product registration screen, and then click "Register Now." Find your Bitdefender license key on your MyBitdefender account, in your purchase email or on your Bitdefender product's installation disc case.
Sign in to your MyBitdefender account on the product activation screen to activate your Bitdefender installation. When the Bitdefender user interface shows up, click "Update" to download the latest antivirus definitions to your computer.
Check the MyDevices section on your MyBitdefender account to see your Bitdefender devices, license keys and available license slots.
If you have multiple license slots remaining, you can install Bitdefender on another device normally and use the same license key to register it.
If you still plan on using your old computer after removing Bitdefender, enable Windows Defender to stay protected. To enable Windows Defender, type "Defender" into the Start screen or Start menu, press "Enter," and then once the Windows Defender window shows, click "Turn On."