With Two Factor Authentication (multi-factor authentication) enabled on Synology NAS, you may not be able to access your device when you authenticate during the login process, if something goes wrong, or if you are verifying. In this case, if you have set up SMTP, you can alternatively send a code to your e-mail address and log in. However, because there is a limit to how to get this code, when you reach this limit, you will receive an “Emergency code limit warning” and the sign-in process will fail. If you don’t have another account with the last alternate admin privilege, then resetting your Synology device is the only solution.
There is no data loss in this reset process. The following configurations are returning to their default. If you have a configuration backup, you can complete this process with minimal workload by restoring it.
- The admin account is restored to default and its 2-factor authentication setting is disabled.
- UI management port is reset to 5000/5001.
- IP, DNS, gateway, and other net interfaces are reset to DHCP.
- PPPoE is disabled.
- Auto Block is disabled.
- Firewall rules are disabled.
- High-availability cluster is removed.
- Virtual Machine Manager cluster is removed.
- Encrypted folders are unmounted and the feature Mount automatically on startup is disabled.
The reset process is left when the “beep” sound is heard by pressing the reset button on the device for 4 seconds. Within 10 seconds, press and hold the RESET button again for 4 seconds until you hear 3 more beeps Wait for about 2 minutes until the STATUS light on your Synology NAS flashes orange or green.
Source: synology