"Why is this error happening to me?"

“Error 123: Unsupported operating system” occurs because the SHA-2 update for Windows 7 has not been applied to your PC. Therefore, if you want to continue using V3, we recommend that you upgrade your Windows to an operating system equipped with SHA-2 (Windows 8, 8.1, 10 or higher).

“I don’t want to upgrade my Windows.”

If for any reason you want to continue using Windows 7 and also want to use V3, we will guide you through installing Windows hotfixes (KB4490628, KB4474419) for Windows 7.

“How can I install KB4490628 and KB4474419?”

Please download and install all patches that match your Windows bit from the Microsoft Update link below.

Hotfix for 32bit
[KB4490628 (for 32bit) hotfix download]
[KB4474419 (for 32bit) hotfix download]

Hotfix for 64bit
[KB4490628 (for 64bit) hotfix download]
[KB4474419 (for 64bit) hotfix download]

- Windows update is performed when installing the hotfix file.

- Problems may occur on your PC during Windows updates, so please back up your important files before installing the hotfix.

- If a problem occurs when installing the hotfix, please contact the PC manufacturer or A/S center.

- You can also apply the contents of this article if “Error 3281f503” occurs when installing V3 on Windows 7.

“What happens if I don’t want to install the hotfix and use it without updating V3?”

We are distributing newly discovered malware information and product patches through V3 engine updates. If you do not update V3, it is difficult to diagnose new/variant malware even if V3 functions are running on your PC. Additionally, you will not receive patches that fix or improve product problems.