> For the complete documentation index, see [llms.txt](https://docs.defguard.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.defguard.net/support-1.md).

# Support

- [How to submit an issue](https://docs.defguard.net/support-1/how-to-submit-an-issue.md)
- [Sending support information](https://docs.defguard.net/support-1/sending-support-information.md)
- [Server applications](https://docs.defguard.net/support-1/sending-support-information/core.md)
- [Desktop Client](https://docs.defguard.net/support-1/sending-support-information/desktop-client.md)
- [Mobile client](https://docs.defguard.net/support-1/sending-support-information/mobile-client.md)
- [Troubleshooting Guides](https://docs.defguard.net/support-1/troubleshooting-guides.md): Before contacting support, check whether your problem is covered here.
- [Core](https://docs.defguard.net/support-1/troubleshooting-guides/core.md)
- [h2 protocol error from reverse proxy](https://docs.defguard.net/support-1/troubleshooting-guides/core/h2-protocol-error-from-reverse-proxy.md)
- [Unable to sign in with correct credentials](https://docs.defguard.net/support-1/troubleshooting-guides/core/unable-to-sign-in-with-correct-credentials.md)
- [User lost access to their 2FA methods](https://docs.defguard.net/support-1/troubleshooting-guides/core/user-lost-access-to-their-2fa-methods.md)
- [Enrollment URL Changed](https://docs.defguard.net/support-1/troubleshooting-guides/core/enrollment-url-changed.md)
- [Failed to parse duration](https://docs.defguard.net/support-1/troubleshooting-guides/core/failed-to-parse-duration.md)
- [Core cannot connect to Gateway or Edge after restart on single-host deployments](https://docs.defguard.net/support-1/troubleshooting-guides/core/core-cannot-connect-to-gateway-or-edge-after-restart-on-single-host-deployments.md)
- [Desktop Client](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client.md)
- [Unix socket permission error on connect (Linux)](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/unix-socket-permission-error-on-connect-linux.md)
- [MFA location disconnected after X-time](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/mfa-location-disconnected-after-x-time.md)
- [High disk usage](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/high-disk-usage.md)
- [Failed to configure DNS (Linux)](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/failed-to-configure-dns-linux.md)
- [Failed to parse IP address](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/failed-to-parse-ip-address.md)
- [Disconnecting shows "Connection failed" (Linux / NetworkManager)](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/disconnecting-shows-connection-failed-linux-networkmanager.md)
- [resolvconf not found (Debian)](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/resolvconf-not-found-debian.md)
- [Unix socket does not exist (Linux)](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/unix-socket-does-not-exist-linux.md)
- [Disconnected after MFA timeout](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/disconnected-after-mfa-timeout.md)
- [Could not start MFA process](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/could-not-start-mfa-process.md)
- [Client connects but cannot reach VPN servers (MTU)](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/client-connects-but-cannot-reach-vpn-servers-mtu.md)
- [Desktop client real-time / auto sync does not work](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/desktop-client-real-time-auto-sync-does-not-work.md)
- [Windows client unable to connect](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/windows-client-unable-to-connect.md)
- ["All traffic" connection issues](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/client-all-traffic-connection-issues.md)
- [Windows installer exit codes](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/windows-installer-exit-codes.md): Desktop Client windows installer exist codes list.
- [Client crashes immediately on launch with "Error 71 (Protocol error) dispatching to Wayland display"](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/client-crashes-immediately-on-launch-with-error-71-protocol-error-dispatching-to-wayland-display.md)
- [Desktop Client connectivity issues](https://docs.defguard.net/support-1/troubleshooting-guides/desktop-client/desktop-client-connectivity-issues.md)
- [Mobile Client](https://docs.defguard.net/support-1/troubleshooting-guides/mobile-client.md)
- [Android "Failed host lookup" error](https://docs.defguard.net/support-1/troubleshooting-guides/mobile-client/android-failed-host-lookup-error.md)
- [Edge Component](https://docs.defguard.net/support-1/troubleshooting-guides/edge-component.md)
- [There was a network error. Can't reach Edge](https://docs.defguard.net/support-1/troubleshooting-guides/edge-component/there-was-a-network-error.-cant-reach-edge.md)
- [Gateway](https://docs.defguard.net/support-1/troubleshooting-guides/gateway.md)
- [No buffer space available](https://docs.defguard.net/support-1/troubleshooting-guides/gateway/no-buffer-space-available.md)
- [TOTP / email codes for MFA do not work](https://docs.defguard.net/support-1/troubleshooting-guides/totp-email-codes-for-mfa-do-not-work.md)
- [WebAuthn security keys](https://docs.defguard.net/support-1/troubleshooting-guides/webauthn-security-keys.md)
- [Can access VPN but not local network or internet](https://docs.defguard.net/support-1/troubleshooting-guides/can-access-vpn-but-not-local-network-or-internet.md)
- [How to verify the VPN is working](https://docs.defguard.net/support-1/troubleshooting-guides/how-to-verify-the-vpn-is-working.md)
- [Testing VPN speed](https://docs.defguard.net/support-1/troubleshooting-guides/testing-vpn-speed.md): VPN Speed Testing Guide: Linux Server & Windows/Linux Clients
- [Server migration and licence transfer](https://docs.defguard.net/support-1/server-migration-and-licence-transfer.md)
- [Troubleshooting Guide V1 legacy backup](https://docs.defguard.net/support-1/troubleshooting.md): Here are some common issues / problems that are frequently encountered.
- [Sending support information](https://docs.defguard.net/support-1/troubleshooting/sending-support-info.md)
- [Client Windows installer exit codes](https://docs.defguard.net/support-1/troubleshooting/windows-installer-exit-codes.md): Desktop Client windows installer exist codes list.
- [Client "All traffic" connection issues](https://docs.defguard.net/support-1/troubleshooting/client-all-traffic-connection-issues.md)
- [WebAuthn security keys](https://docs.defguard.net/support-1/troubleshooting/webauthn-security-keys.md)