Guides
TUN is enabled but there is no network
TUN changes how traffic reaches a client. It cannot make an unavailable node work, and it introduces routing and permission questions beyond a format check.
When this applies
Browsing stops after enabling TUN, only some applications work, or connectivity remains broken after the client exits.
Checks, in order
Restore a known baseline
If you control the device, turn TUN off and check whether the normal connection works. Record the previous setting. If the underlying network also fails, troubleshoot it before changing the client.
Check configuration and selected node
Use the local checker for basic configuration errors, then follow the client’s documented node selection and diagnostics. A parsed configuration is not proof that the chosen server can be reached.
Inspect permissions and competing routes
Follow the client’s official TUN permission instructions. Temporarily stop another personal VPN only if safe. Multiple adapters or overlapping ranges can conflict; do not delete corporate adapters.
Change one setting and restore on failure
Compare the documented system-proxy and TUN modes for the affected application. If the client exits but connectivity stays broken, inspect its documented proxy cleanup steps before altering system settings.
How to interpret the result
Different behavior between modes points toward route coverage, permissions or conflicts, but does not identify a single cause. Keep the last working settings and the exact non-secret error.
When to stop and ask for help
Stop before disabling firewalls, bypassing TLS checks or editing managed routes. Escalate with OS, client version, mode and redacted diagnostics to the administrator or client support.
Related tool
Check a client configuration locallyOfficial references
Based on the linked official documentation, checked 8 September 2026. No client version or device import has been tested for these articles.