I cannot access ANY website hosted in Vercel, except Vercel itself

I cannot access any websites hosted in Vercel from my PC. I've tried all the tests that I can come up with. I've combined VPN, different browsers (webkit, chromium, firefox, etc.)… I thought maybe my ISP was banned, but no, it works just fine in my other devices. Not my IP, because VPN doesn't do the trick. Also, my Mac works just fine.

The websites load all blank. No errors, no network calls. Nothing.

Weirdest part, if I ping the IP it's all good, and if I go to vercel.com itself, it's working just fine. But, if I go to cursor.com for example, which is hosted in Vercel, it won't work. Neither will any other. If I ping the domain directly, it works aswell.

My guess is I'm blocked on a hardware level by Vercel's CDN service for whatever reason? I do zero weird activity on this computer, so I would be surprised. But I really can't think of anything else now.

Anyway, I have a bunch of websites hosted in Vercel and I cannot test production lmao, anyone has had this issue before? I cannot find a lot about it online.

I also tried turning my firewall off, didn't work either.

Network response with SSR website is blank.

Vercel Staff

Hi , welcome to the Vercel Community!

Sorry that you're facing this issue. Can you try opening: https://www.theanshuman.dev/ or https://anshuman-can-ship.vercel.app/ to see if it persists here?

Also, please share what the network request headers look like. And the browser console.

Hello and thanks for the quick response.

https://www.theanshuman.dev/ ==> works https://anshuman-can-ship.vercel.app/ ==> fails

Headers as cURL

1curl ^"https://anshuman-can-ship.vercel.app/^" ^2  -H ^"accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8^" ^3  -H ^"accept-language: en-US,en;q=0.8^" ^4  -H ^"cache-control: max-age=0^" ^5  -H ^"priority: u=0, i^" ^6  -H ^"referer: https://community.vercel.com/^" ^7  -H ^"sec-ch-ua: ^\^"Not(A:Brand^\^";v=^\^"99^\^", ^\^"Brave^\^";v=^\^"133^\^", ^\^"Chromium^\^";v=^\^"133^\^"^" ^8  -H ^"sec-ch-ua-mobile: ?0^" ^9  -H ^"sec-ch-ua-platform: ^\^"Windows^\^"^" ^10  -H ^"sec-fetch-dest: document^" ^11  -H ^"sec-fetch-mode: navigate^" ^12  -H ^"sec-fetch-site: cross-site^" ^13  -H ^"sec-fetch-user: ?1^" ^14  -H ^"sec-gpc: 1^" ^15  -H ^"upgrade-insecure-requests: 1^" ^16  -H ^"user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36^"

reply to #2

I'm not the only one with this issue apparently. I think it's not common, but must be a pattern.

Vercel Alum

Could you go through this post? It may be related!

https://community.vercel.com/t/resolving-ip-blocking-issues/171

Nope, this isn't working. I had already tried different VPNs. I think it's at OS level.

Extra findings:

All browsers are failing. If I go to the networks tab, there's not even a content fetch. However, if I call websites from postman, I get the normal response.

So it's only failing on browsers.

Leaderboard GOAT

What DNS provider are you using on the device where this fails? Strange that it still fails in a VPN...

I tried both Google's and Cloudflare's. But still, wouldn't this affect the Postman call if it was because of DNS?

When I fetch the content using postman, it works. It seems to be browser-only.

Leaderboard GOAT

That's very strange. I'd think it's more likely for Vercel to block a request from Postman than from a browser…

reply to #5

Just to be clear, this isn't IP related, I'm 100% now : )

reply to #10

The thing is, I don't get blocked. Or at least it doesn't seem like I am. But the response's body is empty. just get headers.

1access-control-allow-origin:23*45age:676591489cache-control:1011no-cache, no-store, must-revalidate1213content-disposition:1415inline1617content-encoding:1819br2021content-length:222312425content-type:2627text/html; charset=utf-82829date:3031Sat, 08 Mar 2025 16:11:44 GMT3233etag:3435W/"674fe66552b985d0f05ad4ca9b82539f"3637expires:383904041pragma:4243no-cache4445server:4647Vercel4849strict-transport-security:5051max-age=630720005253vary:5455RSC, Next-Router-State-Tree, Next-Router-Prefetch, Next-Router-Segment-Prefetch5657x-frame-options:5859SAMEORIGIN6061x-matched-path:6263/research/crossing_the_uncanny_valley_of_voice6465x-vercel-cache:6667HIT6869x-vercel-id:7071cdg1::fnjrk-1741450304006-8dbaefd66818

reply to #2

New fun update. I installed wsl and ran a chromium instance in wsl. I'm able to run vercel sites here. It's only on Windows that's not letting me.

Here I'm running everything in the same variables, except for the OS. The right is an Ubuntu distro using WSL, while the left is just windows. So I think it's gotta do with Windows (as usual…)

Vercel Staff

Hi , thanks for sharing your findings here.

No problem, I wish I had a solution too.

I tried making a new session for Windows, all blank. Vercel sites work there. So it's not the OS.

So far I can rule out:

OS
Specific browser (tried all)
DNS (I flushed and changed to Google's and Cloudflare's, same result)
Firewall (I turned it off, no luck)
IP (tried VPN)
My session being banned (If I request the site on postman or even on a fetch() function, I get the proper response)

I'm just stunned, I don't know what else to try.

Any ideas are welcome

Accepted answer

I finally solved it. There was something corrupt affecting my session.

I ran sfc /scannow as admin and it did the trick. I have no clue why, but something there was messing with the specific combination of using any browser on this Windows session.