How to Fix VPN Error 691 (Access Denied)
By Jordan Kim
· About Zone Desire
Quick answer
VPN error 691 means the VPN server rejected your username or password, or the authentication method does not match. Re-enter your credentials, check the domain name, and match the authentication settings (for example MS-CHAP v2) with the server.
What does “VPN Error 691” mean?
The remote connection was denied because authentication failed.
What causes it?
- Wrong username or password
- Missing domain name
- Authentication protocol mismatch
- Account expired or not allowed VPN access
Steps to try
Stop when the issue is resolved.
- Re-type the username and password carefully.
- Add the domain if needed (DOMAIN\username).
- Open the VPN adapter → Properties → Security → allow the protocol your server uses (often MS-CHAP v2).
- Ask your admin if your account has VPN access.
- Delete and recreate the VPN connection.
Need more support? Check the official help: Microsoft Support: Fix Wi-Fi connection issues
FAQs
Is 691 a network problem?
No. The server was reached but refused your login.
Does caps lock matter?
Yes. Passwords are case-sensitive.