Remote-access Guide

remote access vpn troubleshooting

by Beaulah Cronin Published 2 years ago Updated 1 year ago

Remote Access (VPN and AOVPN) troubleshooting guidance

  • Recommended troubleshooting steps. VPN deployment typically requires a minimum of manual configurations on a server or...
  • Troubleshoot Remote Access VPN issues. Event ID: 20227 with error code 720 - VPN clients don't complete a VPN connection...
  • Troubleshoot AOVPN issues. Error code: 800 - The remote connection was...

VPN Troubleshooting Guide – How To Fix VPN Problems
  1. Restart the VPN Software.
  2. Clear your Device of Old VPN Software.
  3. Make Use of the VPN's Help Function.
  4. Make Sure Your VPN is Up To Date.
  5. Change the VPN Server.
  6. Connect Using a Different VPN Protocol.
  7. Check Your Firewall.
  8. Try the OpenVPN Client Instead.
Jan 6, 2022

Full Answer

Why can't I make a remote VPN connection?

The remote connection was not made because the attempted VPN tunnels failed. The VPN server might be unreachable. If this connection is attempting to use an L2TP/IPsec tunnel, the security parameters required for IPsec negotiation might not be configured properly. Possible cause.

How to fix remote access VPN key not entered correctly?

Re-enter a key to be certain that it is correct; this is a simple solution that can help avoid in-depth troubleshooting. In Remote Access VPN, check that the valid group name and preshared key are entered in the CiscoVPN Client. You can face this error if the group name/ preshared key are not matched between the VPN Client and the head-end device.

How do I troubleshoot always on VPN?

Troubleshoot Always On VPN. If your Always On VPN setup is failing to connect clients to your internal network, the cause is likely an invalid VPN certificate, incorrect NPS policies, or issues with the client deployment scripts or in Routing and Remote Access.

How to troubleshoot Ra VPN issues?

Enable NAT-Traversal (#1 RA VPN Issue) Test Connectivity Properly Enable or Disable ISAKMP Keepalives Re-Enter or Recover Pre-Shared-Keys Mismatched Pre-shared Key Remove and Re-apply Crypto Maps Verify the ISAKMP Identity Verify Idle/Session Timeout Verify the ISAKMP Policies Verify that Transform-Set is Correct


Why is the VPN not connecting?

Failure to connect to the internet with a VPN is often caused by firewalls, blocked ports, outdated VPN software, or simply a failure of your router. Make sure that your firewall allows for use of the VPN, that your VPN software is updated, and that the right ports aren't blocked.

How does remote access work with VPN?

A remote access VPN works by creating a virtual tunnel between an employee's device and the company's network. This tunnel goes through the public internet but the data sent back and forth through it is protected by encryption and security protocols to help keep it private and secure.

Why does my VPN keep disconnecting and reconnecting?

If your VPN keeps disconnecting and reconnecting, it's likely that data packets are being lost or blocked between your device and the VPN server. This could be due to issues with the VPN client, your router, or your network connection.

How do I setup remote access to VPN?

Configure Remote Access as a VPN ServerOn the VPN server, in Server Manager, select the Notifications flag.In the Tasks menu, select Open the Getting Started Wizard. ... Select Deploy VPN only. ... Right-click the VPN server, then select Configure and Enable Routing and Remote Access.More items...•

What is the difference between VPN and remote access?

A VPN is a smaller private network that runs on top of a larger public network, while Remote Desktop is a type of software that allows users to remotely control a computer. 2. Remote Desktop allows access and control to a specific computer, while VPN only allows access to shared network resources.

Should I leave VPN on all the time?

VPNs offer the best online security, so you should leave your VPN on at all times to protect yourself against data leaks and cyberattacks, while you're using public W-Fi, and against intrusive snoopers such as ISPs or advertisers. So always keep your VPN on. Always use a VPN when you go online.

How do I change VPN protocol?

AndroidOpen the Proton VPN app and go to ≡ → Settings.Toggle the Smart Protocol switch on or off. To manually select your VPN protocol, toggle it off.If Smart Protocol is disabled, you can manually choose which VPN protocol to use. ... Select the VPN protocol you would like to use from the list.

Does VPN allow remote access?

A remote access Virtual Private Network (VPN) allows users working remotely to access and use applications and data residing in the corporate data center,headquarter offices, and cloud locations, often encrypting all user traffic.

Does VPN allow you to access a computer remotely?

In order to fully secure a remote desktop, a VPN is the best option. With a VPN like Access Server, you have secure access to the network, and then the VPN server has least a privilege access policy setup that would limit an employee to using a remote desktop to connect only to his or her computer's IP address.

Can you be tracked if you use VPN?

However, if you use a poor quality VPN, you could still be tracked. A premium quality VPN encrypts data and hides your IP address by routing your activity through a VPN server; even if someone tries to monitor your traffic, all they'll see is the VPN server's IP and complete gibberish.

Which VPN is best for remote access?

Perimeter 81 – Best all-round business VPN. Jul 2022. ... GoodAccess – Security Strategy Options. Apps Available: ... ExpressVPN – Lightning Fast VPN. ... Windscribe – VPN with Enterprise-Friendly Features. ... VyprVPN – Secure VPN with Business Packages. ... NordVPN – Security-first VPN. ... Surfshark – VPN with Unlimited User Connections.

How to fix VPN not working?

Try disabling, or even better, uninstalling any previous VPN software packages that you might have used, and see if this resolves your issue.

What to do if VPN is slow?

If restarting doesn't help, try reinstalling the VPN as an additional measure: This has been known to help if a VPN is slow to connect, if it crashes frequently, or if the VPN connects to the client network but does not allow the user to perform actions like opening links. 2. Clear your Device of Old VPN Software.

How to get VPN to work again?

1. Restart the VPN Software. Yes, it’s a cliche, but closing down your software can get things running smoothly again. If your VPN has its own program, close it down (all the way, make sure it’s not just minimized on your computer), and restart it. If the VPN is a browser plug-in, close your browser down and restart it.

What to do if you have issues with your connection?

If there are issues with your connection, playing with the protocol settings can be the solution. Experiment with changing the protocol in the settings to see if this resolves your issue. It could even lead to a faster connection.

Can a VPN access a blocked site?

Make sure your VPN is able to access the service you’re trying to use. Although VPNs are incredibly sophisticated at circumventing geographically blocked sites, the sites themselves can be just as clever.

Can you use a VPN to connect to different servers?

Luckily, VPNs make it easy to connect to different servers, so give another one a go. Don’t worry if you’re using a certain country’s location to access content – any VPN worth its salt will offer a multitude of servers in the same country, so you shouldn’t have any issues finding another.

Is VPN software updated?

VPN software is regularly updated. Some of these take the form of quality of life tweaks to make the program easier to use, but others will be essential for the day to day functionality of the VPN, so it’s important to make sure that you don’t ignore update requests.

Why does my VPN have routing issues?

Note: The routing issue occurs if the pool of IP addresses assigned for the VPN clients are overlaps with internal networks of the head-end device. For further information, refer to the Overlapping Private Networks section .

Why is there no VPN tunnel?

If there is no indication that an IPsec VPN tunnel comes up at all, it possibly is due to the fact that ISAKMP has not been enabled. Be sure that you have enabled ISAKMP on your devices. Use one of these commands to enable ISAKMP on your devices:

Why does IPSEC VPN have padding error?

The issue occurs because the IPSec VPN negotiates without a hashing algorithm. Packet hashing ensures integrity check for the ESP channel. Therefore, without hashing, malformed packets are accepted undetected by the Cisco ASA and it attempts to decrypt these packets. However, because these packets are malformed, the ASA finds flaws while decrypting the packet. This causes the padding error messages that are seen.

How to enable NAT-T on VPN?

Choose Configuration > Tunneling and Security > IPSEC > NAT Transparency > Enable: IPsec over NAT-T in order to enable NAT-T on the VPN Concentrator.

How to check if a VPN tunnel is established?

If the tunnel has been established, go to the Cisco VPN Client and choose Status > Route Details to check that the secured routes are shown for both the DMZ and INSIDE networks.

Do remote access users have internet?

Remote access users have no Internet connectivity once they connect to the VPN .

Is excludespecified only for Cisco VPN?

Note: The option excludespecified is supported only for Cisco VPN clients, not EZVPN clients.

How to resolve remote access VPN server name?

Can you resolve the Remote Access/VPN server name to an IP address? In Control Panel > Network and Internet > Network Connections, open the properties for your VPN Profile. The value in the General tab should be publicly resolvable through DNS.

Why is my VPN not connecting to my network?

If your Always On VPN setup is failing to connect clients to your internal network, the cause is likely an invalid VPN certificate, incorrect NPS policies, or issues with the client deployment scripts or in Routing and Remote Access. The first step in troubleshooting and testing your VPN connection is understanding the core components of the Always On VPN infrastructure.

What to do if VPN server name doesn't match certificate?

Possible solution. Verify that the server certificate includes Server Authentication under Enhanced Key Usage. Verify that the server certificate is still valid.

Why is my VPN connection not made?

The remote connection was not made because the attempted VPN tunnels failed. The VPN server might be unreachable. If this connection is attempting to use an L2TP/IPsec tunnel, the security parameters required for IPsec negotiation might not be configured properly. Possible cause.

What is the application log on a VPN?

The application logs on client computers record most of the higher-level details of VPN connection events.

Where is the certificate installed on a VPN?

If you use domain credentials to log on to the VPN server, the certificate is automatically installed in the Trusted Root Certification Authorities store . However, if the computer is not joined to the domain or if you use an alternative certificate chain, you may experience this issue.

Does RAS have server authentication?

The machine certificate used for IKEv2 validation on the RAS server doesn't have Server Authentication under Enhanced Key Usage.


Install the appropriate client from the Download and Install VPN page.

Connection to VPN

Error – "Could not connect to server. Please verify Internet connectivity and server address is correct."


Action – Verify you are entering the correct username and password (Active Directory/ Citrix/ HS login). Go to and login with your username and password. If you are able to login to this site, your username and password is correct.

Mapping Network Drive

Error – Keeps prompting for username and password and doesn't go any further.

More resources

If you have questions about any of these resources please contact the Technology Operations Center (TOC). The TOC provides IT support 24 hours a day, 7 days a week.

What to do if VPN won't connect?

When your VPN won't connect, try these solutions: Check your internet connection. In may seem obvious, but make sure your network connection is working. In particular, if your Wi-Fi connection isn't working, check whether your device is connected to the correct access point. Check your login credentials.

What to do if VPN server doesn't work?

If changing the VPN server doesn't work, restart the VPN software or browser plug-in. Don't just disconnect from the VPN server; quit and restart the software. In the case of browser plug-ins, fully close down and reopen the browser. You may need to clear your browser cache to get the plug-in working again.

How to eliminate browser based issues?

To eliminate common browser-based issues, use a browser that's supported and endorsed by your VPN provider. Also, make sure that you have the latest browser updates installed. Reinstall the latest VPN software package. If nothing else has worked to this point, reinstall the VPN software.

What ports do VPNs need?

In particular, IPSec VPNs need to have UDP port 500 (IKE) forwarded and protocols 50 (ESP) and 51 (AH) opened .

How to find VPN information?

Check your router's manual or website documentation for anything that says VPN, and you should be able to find the information you need. If in doubt, contact your VPN provider.

Does VPN work without a hitch?

Most of the time, VPN services work without a hitch. So, it can be confusing or frustrating if you suddenly have trouble connecting to your VPN. When your VPN is acting a little cranky and refusing to connect, this step-by-step troubleshooting guide can help you get up and running again.

Can VPN be down?

However, sometimes the server you're trying to connect to is having issues. It may be down temporarily or burdened with too many connections. Try a different server and see if that resolves the problem. Restart the VPN software or browser plug-in.

How to check if IPSEC tunnels are working?

If you want to see if the IPSec tunnels are working and passing traffic, you can start by looking at the status of Phase 1 SA. Type show crypto isakmp sa detail, as demonstrated in Example 16-50. If the ISAKMP negotiations are successful, you should see the state as AM_ACTIVE.

How to check IPSEC SA?

You can also check the status of the IPSec SA by using the show crypto ipsec sa command, as shown in Example 16-51. This command displays the negotiated proxy identities along with the actual number of packets encrypted and decrypted by the IPSec engine.

What happens if NAT-T is not negotiated?

If NAT-T is not negotiated or a NAT/PAT device is not detected, they display the Remote end is NOT behind a NAT device. This end is NOT behind a NAT device message, as shown in Example 16-55. Example 16-55. debug Output to Show NAT-T Discovery Process.

How does a client request mode-config?

The client requests mode-config attributes by sending a list of client-supported attributes, as shown in Example 16-57. Cisco ASA replies back with all of its supported attributes and the appropriate information.

What happens after NAT-T?

After NAT-T negotiations, Cisco ASA prompts the user to specify user credentials. Upon successful user authentication, the security appliance displays a message indicating that the user (ciscouser in this example) is authenticated, as shown in Example 16-56.

How to allow VPN access to a network?

To allow a user to access the entire network, go to the Routing And Remote Access console and right-click on the VPN server that's having the problem. Select the Properties command from the resulting shortcut menu to display the server's properties sheet, and then select the properties sheet's IP tab. At the top of the IP tab is an En able IP Routing check box. If this check box is enabled, VPN and RAS users will be able to get to the rest of the network. If the check box is not selected, these users will be able to access only the VPN server, but nothing beyond.

What are the problems with VPN?

There are four types of problems that tend to occur with VPN connections. These include: 1 The VPN connection being rejected. 2 The acceptance of an unauthorized connection. 3 The inability to reach locations that lie beyond the VPN server. 4 The inability to establish a tunnel.

How to check if VPN is authenticated?

For a Windows XP system, right-click on the VPN connection and select the Properties command from the resulting shortcut menu. This will reveal the connection's properties sheet. Now, select the properties sheet's Security tab, select the Advanced radio button, and click the Settings button to reveal the available authentication methods.

How to ping a VPN server?

Once you've verified that the necessary services are running, try pinging the VPN server by IP address from the VPN client. You should ping by IP address initially so that you can verify that basic TCP/IP connectivity exists. If the ping is successful, then ping the server again, but this time ping by the server's fully qualified domain name (FQDN) rather than by its address. If this ping fails where the IP address ping succeeded, you have a DNS problem, because the client is unable to resolve the server's name to an IP address.

What happens if a VPN server doesn't join the domain?

If the VPN server hasn't joined the domain, it will be unable to authenticate logins. You also need to take a look at IP addresses. Each Web-based VPN connection actually uses two different IP addresses for the VPN client computer. The first IP address is the one that was assigned by the client's ISP.

How to check if VPN is rejecting client connections?

You can check this by opening the server's Control Panel and clicking on the Administrative Tools icon, followed by the Services icon.

Why is my VPN connection rejected?

If your VPN server is rejecting client connections, the first thing you need to do is to check to make sure the Routing And Remote Access service is running. You can check this by opening the server's Control Panel and clicking on the Administrative Tools icon, followed by the Services icon.

How to access remote access in Server Manager?

In Server Manager, click Tools, and then click Remote Access Management.

What happens if you turn off IP Helper?

Turning off the IP Helper service will cause a serious error on the Remote Access server. The monitoring dashboard will show the operations status of the server and the details of the issue.

How to enable iphlpsvc?

To enable the service, type Start-Service iphlpsvc from an elevated Windows PowerShell prompt.

How to see what is working on IP?

You will see the list of components with green or red icons, which indicate their operational status. Click the IP-HTTPS row in the list. When you selected a row, the details for the operation are shown in the Details pane as follows:

How to start IP Helper?

In the list of Services, scroll down and right-click IP Helper, and then click Start.

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