assign these available licenses to an expired PC

Hello,
I have a triple license in my account.
There are still two licenses available.

Now I would like to assign these available licenses to an expired PC.

When I go to Manage Devices in the available license and want to add a device, I can only download or send links by email.
I cannot select the existing device.

According to the help section, this should be possible. What am I doing wrong?
The device (my father-in-law's) will be gone for an hour.
The device with the expired license is in my account.

Thanks, Daniel

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Hi Daniel — it sounds like you’re doing everything right. Unfortunately, Trend Micro doesn’t let you directly reassign a new license to an existing expired device.

You’ll need to remove the expired device from your account first, then reinstall Trend Micro on that same PC using one of your available licenses (via download or email link). Once it’s activated, it will appear under the new license in your account.

Hello,
 

You can activate your new Trend Micro Maximum Security license without uninstalling the program.

To update your serial number:

1. Open Trend Micro Maximum Security.

2. Click the expiration date located at the lower-right corner.

3. Select Change your activation code, enter your new serial number, and click Apply to activate your license.

You seem to be doing a fantastic job. Regrettably, Trend Micro does not permit the direct assignment of a new license to an existing device that has expired.

Before you may reinstall Trend Micro on the same PC using one of your available licenses, you'll need to delete the expired device from your account. You can do this by downloading or clicking on an email link. It will show up in your account under the new license once it's activated.

Hello,
 

You do not need to reinstall Trend Micro if it is already installed on your computer. If you have purchased a new subscription, you can simply follow the steps below to update the serial number in your existing Trend Micro Maximum Security installation—no reinstallation required: How to Easily Change Your Trend Micro Activation Code on Windows | Trend Micro Help Center

However, if Trend Micro Maximum Security is not currently installed on your device, you will need to install it using the link below:

My Trend Micro Account - Access features and subscriptions

If you need further assistance, feel free to let us know.