Activating/Registering ESET Smart Security or ESET NOD32 Antivirus—FAQ

KB Solution ID: KB103 |Last Revised: October 5, 2015

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Frequently Asked Questions:

I have a 3-computer license and receive an error during activation - what do I do?
If you receive an error message (such as "Activation failed") during activation, it is likely because you already used your key when you installed your first computer. After activating your first computer with the activation key, you should receive an email from ESET with your Username and Password which should then be used to activate your remaining computers (reinstallations of ESET also require that you use your Username and Password).

When installing and activating on your second and third machines, follow the steps below:

  1. On the second computer, insert your CD into the second machine or select your product from the Download page to begin your second installation.
  2. Follow the on-screen instructions to install your product.
  3. When you reach the Product Activation window, be sure to select Activate using Username and Password and complete the installation using your ESET-issued Username and Password.
  4. Repeat steps a-c for your third installation.

How do I activate my ESET product?
If you purchased your ESET product from a third-party vendor, you must activate the software to receive a valid Username and Password.

Do I need to activate my ESET product?
If you already received a Username and Password from ESET then you do not need to register your serial number / activation key again, but make sure that you enter your Username and Password into your ESET security product. Without a properly entered Username and Password, you will not be able to receive the virus signature updates that are critical for maximum protection.

What password should I use when completing the online form?
The password for the activation form is made up by you and is unrelated to the ESET Username and Password that will be emailed to you upon successful completion of the activation form.

I receive the error message telling me that my serial number or activation key I entered is incorrect.

  • Make sure to enter the serial number/activation key exactly as it appears.
  • Your serial number/activation key is case sensitive and any hyphens are necessary. A big "0" is the number zero (0), a little "o" is the lowercase letter o.

How do I know if I have successfully completed the activation process?


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