How to unblock a website: what works
Why a site won't open: DNS, SNI/DPI, IP or protocol blocks. How to test it, switch to encrypted DNS, and what a local tool can't fix.
"How do I unblock this website?" is one of the most common questions people type into a search box, and most answers jump straight to "install a VPN". That is often the wrong first step. A page that will not load is a symptom, and the same symptom can come from a typo, a broken router, an overloaded server or a deliberate block. This guide explains the common kinds of blocking in plain language, which ones a local tool can handle, and a step-by-step routine you can follow on your phone.
One thing up front: GreenTunnel is a local VPN. It runs on your device, there is no relay server run by us, and it does not hide your IP address. It does not promise to open any particular site or get around any country's firewall. It fixes a specific set of problems, and this article is honest about which.
Why a website fails to open
Before blaming a block, rule out the boring causes: the site is down, your connection dropped, the address is mistyped, or your device's date and time are wrong (which breaks HTTPS certificates). If the same site opens on another network, such as mobile data instead of Wi-Fi, something on the first network is involved. Then it is worth asking which kind of block it is.
1. DNS blocking
Your device first asks a DNS resolver (usually run by your ISP or your router) for the site's IP address. A network that blocks by DNS simply gives a wrong answer: no answer at all, an address that leads to a block page, or an unrelated address that never serves the site. The site itself is fine and its real address is reachable. This is the cheapest kind of block to deploy, so it is very common on home routers, school networks and some ISPs.
What helps: asking a different resolver, ideally over an encrypted channel (DoH or DoT), so the answer cannot be rewritten on the way.
2. SNI and DPI filtering
When you connect over HTTPS, the first message of the TLS handshake normally contains the site's name in plain text. This field is called SNI. A filter that uses deep packet inspection (DPI) reads it and drops or resets the connection if the name is on a list. The page content is still encrypted, but the name is visible. Details are in What is DPI.
What helps: sending that first message in a different shape, for example splitting it into pieces so a simple filter does not recognise the name. This is what GreenTunnel's techniques do. It works only against filters that match the name in the first packet, and filters change over time.
3. IP blocking
Some networks block by destination address. Packets to that IP are dropped no matter what name you used, so the connection simply times out. Encrypted DNS does not help because you already know the right address. Splitting packets does not help because the packets never leave the network.
What helps: only sending traffic through a different server, one you choose and trust. That means a proxy or a tunnel, which is a different product category from a local DPI tool. GreenTunnel offers Proxy Route and Tunnel Link for servers you run or rent yourself.
4. Protocol, port and whole-service blocks
A network can block a protocol (for example QUIC on UDP port 443, which makes sites fall back to TCP), a port, or an entire category of traffic. A shutdown or a "white-list only" network is the extreme case. A local tool cannot help with these, because it still needs the network to carry the traffic.
| Kind of block | What you usually see | Can a local tool help? |
|---|---|---|
| DNS | "Server not found", a block page, or a wrong site | Yes, with encrypted DNS |
| SNI / DPI | Connection reset or timeout only on HTTPS | Often, by reshaping the first packets |
| IP address | Timeout on every attempt, even with correct DNS | No. Needs another server |
| Protocol, port, shutdown | Many sites or apps fail together | No |
Step-by-step: what to try, in order
- Retest on another network. Switch between Wi-Fi and mobile data. If it opens on one, the problem is local to the other. See why a site can open on mobile data but not on Wi-Fi.
- Run Inspect URL. Open the Inspect URL tab in GreenTunnel, type the domain and tap Inspect. It compares your ISP's DNS with encrypted DNS, tries to reach the real IP, and tests HTTPS with and without bypass. It names the likely cause in plain words. How to read it: Is a site blocked on your network?
- Switch to encrypted DNS. In Settings → DNS choose a DoH or DoT provider. When GreenTunnel's protection is on, every DNS lookup on the device goes to the server you picked. This alone solves DNS blocking.
- Turn on protection. Start the VPN from the Home screen. If Inspect URL found a working technique, tap Use this technique. You can review it later under Settings → Technique.
- Use Always direct for sites that break. A few services, such as some banks, dislike any modified traffic. Add their domains to Always direct. Those connections skip proxies and packet reshaping entirely. See routing rules.
- Check Requester. Open the site, then look at Requester. It shows how each connection was handled: Bypass, Direct or Error. A pile of errors for one domain points to an IP or protocol block.
If it still fails, follow Site still blocked with GreenTunnel on?
What not to expect
- No promise for any country or site. Blocking methods differ between ISPs and change often. A technique that works today may stop working next month.
- No IP hiding. Websites still see your real IP address unless you deliberately route through a proxy or tunnel you chose.
- No help against shutdowns, IP blocks or white-list networks. Local tools can't create connectivity that the network refuses to carry.
- No anonymity. This is a connectivity and DNS tool, not an anonymity tool.
Is a remote VPN the answer instead?
Sometimes. If the block is by IP address, or you need to appear in another country, a remote VPN or your own server is the realistic option. If the block is DNS or SNI-based, a local tool is lighter: nothing is detoured, so speed stays close to your normal connection. We compare the two models in local VPN vs remote VPN and in Do I need a VPN?
GreenTunnel is free on Android and iPhone, with optional Premium for extra routing features. Learn more on the home page.
FAQ
How do I know which kind of block I have?
Compare results. If a different DNS resolver returns a different, working address, it is DNS blocking. If the address is correct but only HTTPS fails with a reset, it points to SNI filtering. If connecting to the correct address always times out, it is likely an IP block. Inspect URL runs these checks for you.
Will changing my DNS to 1.1.1.1 or 8.8.8.8 be enough?
For DNS blocking, usually yes, as long as the network lets DNS queries leave. Some networks redirect plain DNS on port 53 to their own server, which is why encrypted DNS is more reliable. It does nothing for SNI or IP blocks.
Does unblocking a site hide my identity?
No. Fixing DNS or reshaping packets changes how your connection starts, not who you are. The site and your ISP can still see your IP address and the destination you connect to.
Is it legal?
That depends on where you live and which network you are using. Check your local laws and the network's rules before you bypass any filter.
Sources
- IETF, RFC 8484: DNS Queries over HTTPS (DoH).
- IETF, RFC 8446: TLS 1.3 (the ClientHello and the server_name extension).
- IETF, RFC 9000: QUIC (QUIC runs over UDP, which is why sites can fall back to TCP when UDP is blocked).
