To switch KuaiLian protocol, open Settings → protocol / connection method, leave Auto, pick WireGuard or OpenVPN (UDP/TCP if listed) once, save, and reconnect on the same node. If one protocol spins and fails, note the name and try another. When every protocol fails, widen to network and nodes—do not treat a switch as a speed or streaming guarantee.
Last week in a café, a coworker left KuaiLian on Auto and the handshake spun forever. They blamed the node; the Wi-Fi was choking UDP. OpenVPN TCP from the in-app list reached Connected on the same node. The reverse happens too: WireGuard flies at home, office nets only accept TCP. The protocol menu decides how the tunnel is built—not which country is forever fastest.
Full connect still fails and you also need DNS/firewall checks? Use connection troubleshooting. Already Connected but browsing, downloads, or meetings feel slow: slow-speed guide. Sites load but you worry lookups still hit local DNS: DNS leak check. Client never launches: auto-connect / startup. This page is only for how to switch protocol and WireGuard/OpenVPN connect-fail contrasts—no node-speed or streaming-unlock claims.
Protocol switch vs can’t connect vs feels slow
- Protocol switch: you need to change WireGuard / OpenVPN (or Auto → manual), or one protocol never connects
- Can’t connect: protocol changes still fail; you also need DNS, firewall, node lists → connection guide
- Feels slow: status is Connected; the pain is throughput/latency → slow-speed guide with VPN-off tests
Name the symptom before you touch menus: can’t switch / one protocol handshake fails, every protocol fails, or connected-but-slow. Keep the first here; send the others to connection and speed articles so three pages do not fight over the same clicks.
Find the real protocol menu in your build
Labels differ. Look under settings / connection / advanced for Protocol, connection protocol, or transport. The list may show Auto, WireGuard, OpenVPN, OpenVPN UDP, OpenVPN TCP—use what this device shows, not outdated screenshots.
1. Snapshot the current value
Auto or a named protocol. Screenshot before edits so you can roll back.
2. Keep the same node
Do not swap regions during a contrast—or you will not know if protocol or node moved the needle.
3. Change only protocol
Do not clear cache, flip Kill Switch, and rewrite split lists in the same pass.
4. Save, then reconnect
Some builds need a full disconnect/reconnect; Save alone may keep the old tunnel.
Leave Auto for WireGuard or OpenVPN
- Fully disconnect (status shows Disconnected)
- Open the protocol menu, leave Auto, pick WireGuard or OpenVPN (if UDP/TCP are split, note which line you chose)
- Return to the main screen and Connect on the same node
- On success, log “network + protocol”; on failure, keep the node, try another listed protocol once
Auto is fine most days, but on restricted Wi-Fi it can pick exactly the path the firewall blocks. A manual pick tells you which protocol works here. Missing a name you saw online? Check the download page for the current build—older packages may list fewer options.
WireGuard will not connect: contrast checks
Prove whether the handshake completes—this is not a download-speed test.
- Same node, WireGuard spins past ~30–40 seconds: note the time, switch to OpenVPN (prefer TCP if listed), reconnect once
- WireGuard fails immediately with a permission prompt: confirm the OS still allows VPN configuration; revoked permission can block any protocol, but sometimes only shows on one path
- Only a few nodes fail on WireGuard while others work: lean node-side—try 1–2 peers on the same protocol, not a world tour
- Every WireGuard node fails but OpenVPN TCP works: the network likely limits UDP—save TCP as the manual default for that network
Ignore review screenshots that crown WireGuard “always fastest.” This article does not rank protocol speed.
OpenVPN will not connect: UDP vs TCP
If the list splits OpenVPN into UDP / TCP, match the network—not what “sounds better.”
- OpenVPN UDP: like WireGuard, hotel/campus nets that hate UDP often stall the handshake
- OpenVPN TCP: many restricted nets only pass TCP; when WireGuard and OpenVPN UDP both fail, use TCP as the contrast
- TCP works, all UDP-style options fail: keep TCP as that network’s manual default; re-test when you change networks instead of locking forever
- UDP and TCP both fail: you are past “protocol only”—move to connection troubleshooting (DNS, firewall, version, node list)
Connected but almost nothing loads? Separate tunnel issues from DNS/proxy via connected but no internet—do not idle-flip the protocol menu.
How this splits from connection and slow-speed guides
- This page: how to switch; WireGuard / OpenVPN connect-fail contrasts
- Connection guide: protocols already tried, still cannot connect → DNS, nodes, firewall, version
- Slow-speed guide: already Connected; you care about browsing/download/meeting feel → VPN-off contrast; protocol is only one variable
The connection article may say “try another protocol” as one step; detailed WireGuard/OpenVPN contrast lives here. Slow-speed protocol trials ask “did the task feel better?”—they do not replace the connect-fail switch flow.
Still wrong: what to record before FAQ / download
If contrasts still fail, gather this for FAQ or in-app support:
- Device, OS, KuaiLian version, and install source
- Protocol before/after (Auto, WireGuard, OpenVPN UDP/TCP)
- Per protocol on the same node: success / spin timeout / instant fail
- Network type (home, hotspot, hotel/office Wi-Fi); extra proxy or another VPN (never send passwords)
Protocol list mismatches old tutorials: check the download page first. Reinstall can refresh options; it does not guarantee speed or unlocks. Setup paths: Guides.