How to fix Client Certificate Mapping Authentication error

The client certificate mapping Authentication uses a client certificate to authenticate users. In this article, I will show you how to fix the Client Certificate Mapping Authentication error when upgrading to Veeam ONE v12.1. Please see Map a Network Drive: How to mount a Network Drive, How to create a Mapped Drive via GPO Preferences, and How to Fix The Local Device Name is Already in Use.
To learn what software is required before upgrading Veeam ONE, see System Requirements. When upgrading to Veeam One 12.1, you may run into the error “client certificate mapping authentication” as shown below. With this issue, you cannot proceed with the Veeam ONE upgrade.


Why was this error prompted “Client Certificate Mapping Authentication”
The element is not available on the default installation of IIS 7 and later. This feature allows users to log in to Veeam ONE Web Client with multi-factor authentication (MFA) through client certificate configuration. Therefore, it is required by Veeam ONE for a successful upgrade.
Learn how to fix this network connection does not exist, and video on how to fix WiFi not connecting on Windows 11, and video on how Convert Google Forms Into Microsoft Forms
Resolution “Install Client Certificate Mapping Authentication”
Due to several issues, Veeam was unable to automatically install the “Client Certificate Mapping Authentication” during the upgrade process.
Here are the associated errors resolved: Fix Windows 10 Setup 1809 build 10.0.17763.1 is not supported Error, how to fix Windows update Install error 0x800700b7, Fix Keep personal files and apps option greyed out during Upgrade, and how to fix “Error 0x80073701: The request to add or remove features on the specified server failed“.
As I said, the above fundamental issues need to be fixed. Else, you will not be able to resolve this issue.
To install this feature, use the following steps by launching the Server Manager.

From the Server Manager, click the Manage menu, and then click Add Roles and Features.

Before you begin the page, click on Next. Select Role-based or feature-based installation

On the Select destination server, select a server from the server pool, and click Next. In the select server role, click Next as well.
On the Server Roles page, expand Web Server (IIS), expand Web Server, expand Security, and then select Client Certificate Mapping Authentication. Click Next.


On the Select Features page, click Next.

Select restart destination server if required

On the Confirm installation selections page, click Install.


On the Results page, click Close

As you can see the installation has succeded.

You may want to take a look at how to configure Veeam ONE Web settings, and how to Configure GPS location “Google Map” on your Android Studio Emulator.
I hope you found this guide useful on how to fix the Client Certificate Mapping Authentication error. Please feel free to leave a comment below.