REINSTALL BITDEFENDER TOTAL SECURITY AFTER FORMAT PC
You can either use online installer or offline installer of bitdefender total security 2021
Online installer :
Offline Installer :
32 bit : https://download.bitdefender.com/windows/desktop/connect/cl/2021/all/bitdefender_ts_25_32b.exe
64 bit : https://download.bitdefender.com/windows/desktop/connect/cl/2021/all/bitdefender_ts_25_64b.exe
If you know the bit of your windows you can directly downloads the offline installer accordingly or if you do not have any idea of the bit, you can directly opt for online installer which will download product automatically according to your computer bit.
Once the bitdefender is installed completely on your windows, a central windows will open, where you will have to input your registration/ login details of your bitdefender online central account and it will synchronize with the bitdefender server and activate your product.
Make sure you have the registration/ activation code already registered with the online central account.
Activating bitdefender via online central : https://www.bitdefender.com/consumer/support/answer/1715/
(Bitdefender beta tester 2019/ 2020)