Avatar for Username

Buscar en Ayuda

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Este tema ha sido archivado. Haz una nueva pregunta si necesitas ayuda.

User agent results in 520 error response

  • 3 respuestas
  • 0 tienen este problema
  • 1 visita
  • Última respuesta de Georgergb

Georgergb
Georgergb
more options

Hi,

Someone is trying to visit our website but keeps getting a 520 error response.

It appears that their user agent is being blocked at some point but I don't know why or where (I have tested the user agent in browser tools and get the same response). Yet, using it to visit other websites works fine, likewise if they test using another user agent they can access the site.

We use Cloudflare but I don't think the issue is their end as we have sites hosted elsewhere which can be accessed through the CDN with the same user agent.

Checking the server logs shows no sign of the visitor's IP address accessing the site.

The user agent is: Mozilla/5.0 (Windows NT 6.1; rv:33.0) Gecko/20100101 Firefox/33.0

Just wondering if anyone can suggest how I might be able to narrow down where to find the issue or what I should be looking for? 33 seems like quite an old version, could it be the server doesn't accept visits from an older version?

Many thanks

Hi, Someone is trying to visit our website but keeps getting a 520 error response. It appears that their user agent is being blocked at some point but I don't know why or where (I have tested the user agent in browser tools and get the same response). Yet, using it to visit other websites works fine, likewise if they test using another user agent they can access the site. We use Cloudflare but I don't think the issue is their end as we have sites hosted elsewhere which can be accessed through the CDN with the same user agent. Checking the server logs shows no sign of the visitor's IP address accessing the site. The user agent is: Mozilla/5.0 (Windows NT 6.1; rv:33.0) Gecko/20100101 Firefox/33.0 Just wondering if anyone can suggest how I might be able to narrow down where to find the issue or what I should be looking for? 33 seems like quite an old version, could it be the server doesn't accept visits from an older version? Many thanks

Solución elegida

Hi

Firefox 33 was released in 2014 - it would be very much in their interest (both to access your website, but also for the security of their web browsing) if they updated to a more recent version.

Leer esta respuesta en su contexto 👍 1

Todas las respuestas (3)

Georgergb
Georgergb Autor de la pregunta
more options

Just an addition to my original post:

I have tested various versions of Firefox in Browserstack. Up to and including version 40 result in the 520 error message, versions 41 onwards are able to access the website.

Paul
Paul
  • Top 25 Contributor
  • Moderator
more options

Solución elegida

Hi

Firefox 33 was released in 2014 - it would be very much in their interest (both to access your website, but also for the security of their web browsing) if they updated to a more recent version.

Georgergb
Georgergb Autor de la pregunta
more options

Thanks Paul.

Yes, ideally that would be the outcome. It's a web tool they are using which can access other sites but not ours. I have a feeling our hosting company must have stricter security rules that blocks older browsers.

I have tested various versions and it seems anything up to version 40 does not work, only later versions get access.