Troubleshooting

Fexyn VPN feels slow

Five fixes in order of impact. Most slow connections are fixed by the first two.

First, the baseline

Run a speed test without the VPN connected. Note the number. Then connect Fexyn and run the same test. The gap between them is the VPN overhead. WireGuard on a clean connection typically loses 5–10%. VLESS Reality loses 10–20%. OpenVPN on TCP/443 can lose 30%+ depending on your route.

If the gap is dramatically larger than that, work through the fixes below.

Fix 1 — Pick a closer server

Distance to the VPN server is the dominant factor in latency and a major one in throughput. A server in Frankfurt feels different from a server in Singapore if you're in London.

Open the Fexyn app, switch to a server in your country or the nearest neighbouring one, and re-test. The "closest" server isn't always fastest because routing isn't geography-aware — try two or three options.

Fix 2 — Switch protocol

Each protocol has different overhead:

Fexyn Bolt (WireGuard) — fastest. Use this on clean networks.
Fexyn Stealth (VLESS Reality) — adds 10–20% throughput cost because of the TLS layer. Worth it on filtered networks; not worth it on clean ones.
Fexyn Secure (OpenVPN) — slowest. TCP fallback adds head-of-line blocking when packets are lost. Use only when WireGuard and Stealth both fail.

If you're on Stealth or Secure on a clean network, switch to Bolt. Settings → pin Fexyn Bolt → reconnect.

Fix 3 — Check ISP throttling

Some ISPs throttle VPN traffic specifically, especially during peak hours and on lower-tier plans. The signature: fast speeds in the morning, slow speeds in the evening. If you see this pattern with Fexyn but not without it, your ISP is shaping VPN traffic.

Workaround: use Fexyn Stealth (VLESS Reality). The traffic looks like ordinary HTTPS to a real public site, so ISPs that shape VPN traffic by signature won't recognise it. The throughput cost of Stealth is offset by avoiding the throttle.

Fix 4 — Restart the helper service

The Fexyn Windows app uses a SYSTEM-level helper service for the tunnel. If it's been running for a long time across many connect/disconnect cycles, restarting it sometimes clears stuck state. Quit the app from the system tray, wait five seconds, reopen it.

If that doesn't help, reboot Windows. The helper service restarts cleanly on boot.

Fix 5 — Check system resources

VPN protocols use CPU. On older hardware, a fully-loaded CPU can bottleneck the tunnel even when the network has capacity. Open Task Manager, sort by CPU, and confirm nothing else is consuming most of the cores while you test. Common culprits: Windows Update, antivirus scans, browser tabs running heavy JavaScript.

Bonus — DNS leaks can also feel like slow speeds

If DNS queries are leaking, name lookups can take longer because they race between the leaked path and the tunnel path. Sites feel sluggish even though the tunnel itself is fast. Run [the DNS leak test](/tools/dns-leak-test) and follow [the DNS leak fix guide](/support/troubleshooting/dns-leak) if anything shows up.