VPN issues usually fall into a few patterns: it won’t connect, it connects but there’s no internet, it disconnects randomly, it becomes very slow, or only certain apps/sites fail (banking, streaming, work tools). Another common pattern is “it works on Wi‑Fi but not mobile data” (or the opposite), which often points to carrier/ISP filtering or MTU/protocol problems rather than the VPN account itself.

Before you change settings, define the symptom precisely and note the exact error message (if any), because different symptoms map to different fixes (for example, DNS leaks vs routing vs authentication failures).

Quick diagnosis checklist (fast wins)

Start by confirming your baseline internet works without the VPN: open a few sites, switch Wi‑Fi ↔ mobile data, and complete any captive portal login pages (hotel/cafe networks can block VPN until you accept terms). Next, update the VPN app and your OS, then reboot the device—connection bugs and driver issues are often fixed by updates and a clean restart.

If it still fails, change server location to a nearby server (distance and server overload strongly affect stability and speed), then try another country if a service is blocking that region’s VPN IP ranges. Finally, verify account basics: active subscription, correct login, and that you haven’t exceeded device limits (some providers block new sessions if too many devices are connected).

Technical fixes that solve most cases

Change the VPN protocol when a network blocks or degrades one option: common choices include WireGuard, OpenVPN (UDP/TCP), and IKEv2. Protocols behave differently under firewalls—for example, IKEv2 relies on specific ports (UDP 500/4500 plus ESP), which can be easier for networks to block than OpenVPN, while OpenVPN can be configured on many ports and can use TCP, which may traverse restrictive networks better. WireGuard is usually fast and lightweight but is UDP-based and can be affected by traffic shaping, depending on the network.​

If your VPN “connects but no internet,” focus on DNS and routing: ensure the VPN is pushing usable DNS servers (or set trusted DNS manually), flush DNS cache, and check whether IPv6 is causing leaks or conflicts (some setups behave better with IPv6 disabled). If you get random stalls or partial loading, try lowering MTU (a mismatch can break certain paths and cause “connected but unusable” behavior).

If you use kill switch and split tunneling, understand the interaction: an “internet kill switch” may block all traffic when the VPN is not in the expected state, which can override the intent of split tunneling and make bypassed apps appear “broken.” Use an app-level kill switch (if available) when you need split tunneling, and test rules by temporarily disabling kill switch only long enough to confirm the cause.​

Rules of use, limits, and legal constraints

Follow your VPN provider’s terms and the rules of the services you access: many platforms (especially streaming) actively detect and block VPN IP ranges to enforce licensing, so “VPN not working with Netflix” is often an intentional block rather than a technical failure. For banking, government portals, and some corporate systems, VPN logins can trigger fraud/risk controls; the safest practice is to use a local server (same country) or temporarily disable VPN for that site if permitted.

Legal conditions vary by country and can change quickly; in Russia, reporting indicates VPN use is not presented as an outright general ban, but regulation and penalties around accessing prohibited/extremist content and VPN-related compliance have tightened. If you are in a jurisdiction with restrictions, treat “bypassing blocks” and “accessing prohibited content” as a legal risk area and avoid steps that would violate local law.​

Technical limitations you can’t fully “fix”:

• Some networks block VPN signatures or throttle encrypted tunnels; switching protocols/ports may help, but not always.
• Some VPN endpoints get blocked as soon as they become popular; rotating servers and using provider features (obfuscation/stealth, dedicated IP) may be required if available.
• No VPN guarantees anonymity; it changes who can see your traffic and adds encryption in transit, but it does not make unsafe downloads safe or stop account-level tracking.

User data security and safe configuration

Choose providers and settings that reduce data exposure: avoid weak/obsolete protocols like PPTP (widely considered insecure), and prefer modern options such as WireGuard, OpenVPN, or IKEv2 depending on your threat model and network conditions. Turn on DNS leak protection and test occasionally; DNS leaks can reveal which domains you visit even if your traffic is encrypted.​

Use kill switch when privacy matters (public Wi‑Fi, P2P, sensitive work) so traffic doesn’t “fail open” if the tunnel drops, but confirm it’s configured correctly to avoid self-inflicted outages. Protect your account: strong password, MFA if available, and avoid “free VPN” apps that monetize by collecting data—your VPN provider can see some metadata, so trust and policy matter.