[Solved] VPN Error 691 when connecting Out of the various errors that can plague VPN users, the VPN Error 691 can be among the more technical ones and therefore more challenging to solve. While it generally signals an issue with the username and password you are connecting with, the problem can oftentimes be deeper. Don’t worry, as we’ve covered just about every cause and solution. Editor’s note: do not mistake VPN Error 619 with the VPN Error 691, although they have similar numbers, it’s a completely different issue. Table of Contents Fix #1: Create a new connection and see if it’s still giving you an Error 691Fix #2: Switch to, or enable, Microsoft CHAP Version 2Fix #3: See what’s to do about your logon options and dataFix #4: Tweak the LANMAN settings Fix #1: Create a new connection and see if it’s still giving you an Error 691 We like to start off with easy solutions, and this is definitely the easiest on our list. While Error 619 or something similar can oftentimes be fixed by simply restarting one or more devices, the same is rarely true of Error 691. There is one thing you can do, however. Navigate to the VPN section in the Network & Internet settings on your Windows machine, delete the VPN connection you are using and then find your way to the “Add a VPN connection” button. Set up a new connection that has PPTP (Point to Point Tunneling Protocol) enabled and use it to connect. If it’s fixed by this point, you’re good to go. Another thing you can do is to change the VPN software that your office is currently using with something like Ivacy VPN, which we’ve ourselves used for a long time and can attest to its functionality. While this can be cumbersome if you’re using a lot of machine, it’s a good attempt at a one-stop-shop fix before you move into more complex ones. Fix #2: Switch to, or enable, Microsoft CHAP Version 2 While we did say that the above solution is as far as you get in terms of easy ones, you don’t need to haul in tech support just yet. In a lot of cases, the Error 619 can be fixed by simply enabling the Microsoft CHAP (Challenge-Handshake Authentication Protocol) Version 2 in case you’re still using the v1. To do this, you can either press the Windows Key + X and select “Network Connections” or press Windows Key + R and type in “ncpa.cpl” without the quotation marks and press OK. From here, make your way to the VPN Connection, right click it and select Properties, go to the Security tab and allow the Microsoft CHAP Version 2 near the bottom of the prompt. Fix #3: See what’s to do about your logon options and data If enabling Microsoft CHAP Version 2 still gives you an Error 619 when you’re trying to connect, there could be one or several issues related to your logon data and settings. Depending on where you’re connecting to, you might be required to enter a username and password, and it pays to double-check that these are entered correctly on your machine before trying something else. You might also want to verify that you are connecting directly to your company’s network and not a subsection of it, along with trying to create an entirely new logon ID. Still getting the Error 619 after all of these? Go to the same menu we listed above, but hit the VPN Connection tab instead of Security. Make sure that the “Include windows logon domain” is disabled, and if it’s not, disable it yourself and press OK. Here is where you might also want to update your network drivers (by finding your router in the Network adapters section in Device Manager) before heading towards the most technical fix on our list. Fix #4: Tweak the LANMAN settings Although doing this isn’t that hard, it does signal that you’re running out of fixes you can do yourself, and if you’re still getting the Error 619 afterwards, you’re more than likely to require external help. In the same Run menu we mentioned above that’s accessed by pressing the Windows Key + R, type in secpol.msc and press OK. From here, you’ll have to do a bit of navigation, making your way from the Administrative Tools to Local Security Policy, then Local Policies and finally Security Options. Here, open the Network Security: LAN Manager authentication level, and under the default Local Security Setting, enable the Send LM & NTLM responses only setting and press OK. In the same area, head to Network Security: Minimum Session Security for NTLM SSP, then its Local Security Setting and make sure the Require 128-bit encryption is disabled. After confirming this, you might want to restart your computer depending on how many things you’ve tweaked, and if you’re still getting the Error 619, don’t hesitate to reach out to a tech specialist in your company, as you’ll know you’re dealing with a deeper issue.