If you lack internet access or the online method fails, use the automated phone system. Transfer Office 2013 without a product key - Microsoft Q&A
| Feature | Office 2013 Activation | Office 2021 (LTSC) | Microsoft 365 | | :--- | :--- | :--- | :--- | | | One-time (if you can find a key) | One-time (~$250) | Monthly Subscription | | Security | No security updates (High Risk) | Fully supported | Fully supported | | Activation Ease | Difficult (Server issues) | Easy (Digital License) | Easy (Account Link) | | Device Limit | 1 PC | 1 PC | Up to 5 devices | activation microsoft office 2013