Draytek Vigor2762 Quick Start Manual page 15

This is from Microsoft Edge:
Most other browsers will present equivalent warnings. In each case, following the
prompts/links will allow you to access the router's web interface. It is still encrypted
with SSL/TLS.
Note
The router login prompt will display ask for username and password.
The default login details are:
Username: admin
Password: admin
This warning appears because the router's default certificate is
'self-signed' rather than issued to you by a certificate authority who has
verified your identity. A self-signed certificate means that you cannot
verify the identity of the server, but as it's your own local router, that
shouldn't be an issue - your connection is still encrypted.
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