Some users getting ERR_CONNECTION_RESET error

Hi Cloudflare, I am not sure if I am posting this in the right category or not… b/c I am not really sure what the problem is :slight_smile:

Recently my company has been receiving reports of our JS file not loading for some of our customers (roughly 8). The error logged in their console is always Failed to load resource: net::ERR_CONNECTION_RESET They have tried Chrome, Safari, and Firefox with no luck. I’ve done quite a bit of research into this error but can’t find any useful info.

I am hoping someone here can point me in the right direction. Maybe things to look at, or ways to debug this.

The JS file in question here is: https://api.memberstack.io/static/memberstack.js

We do have Cloudflare enabled for our api.memberstack domain with static asset caching enabled.

Thanks!

Are you users able to to connect the js file by url or are they blocked from that as well?
What is the page they are trying to load which has the file or is it multiple pages?

about 15 days ago google console warned me about a page being not mobile friendly. I tested and found that 1 of my javascript which is present of page and on server was not loading. Now mobile friendly page do not show screenshot on my site.

But when I test on webpagetest same page show screenshot. That javascript error still continues.

tyler3 please share if you find any solution. Would love to try.

@Jake1st thanks for reply.

I’ll try to get an answer on the first question. For the second question, the page is http://www.cataboom.com/login and I am pretty sure the problem happens on all the pages.

I haven’t been able to replicate the issue, but I do know that there are about 8 users that still can’t use the cataboom.com site because our script won’t load.

Thanks!

Do they have any ad blocking extensions enabled?
Additionally, are these users behind a firewall or other type of web filter? A connection reset is a method that firewalls use to block content from being loaded.

Do you have a domain?

@Jake1st they don’t have any ad blocking extensions. I did find out today though that they are able to access our script outside their office. So I am wondering if this is some sort of firewall issue.

I asked them to try accessing the script directly at their office today. I’ll let you know what happens.

If this does turn out to be a firewall issue, what steps can we take to not have our JS file blocked? The user I have been talking to says they have zero issues with other websites.

Thanks for your help with this.

1 Like

Depends on the firewall and why it is blocking it. If the firewall is detecting it as malicious then you might be able to whitelist it or be able to add an exception to the firewall rules for the url

Hi Jake,

They get an error even when they try to visit the script’s URL directly.

image

The image is a bit blurry but it appears that this is the error in the console, “the authority of the received data could not be verified”

Any thoughts on this?

tyler3,

do those user has any different entry for your domain in system host file?

They do not…

That means that there is a certificate issue. Are they doing any HTTPS inspection on their firewall?
Here is a link about a work around:
https://support.mozilla.org/en-US/questions/1068417

Hi Jake,

Are there any solutions that we can do on our end to resolve the “certificate issue”? At this point I am very confident that this problem is specific to us. All users that I have spoken to don’t have any problems with other sites and never had. I find it strange that a firewall is disallowing our script but allowing all other scripts :confused:

Thank you for your help with this. I know it’s something you don’t see everyday.

Do you know if users have the same issue outside their current network? As in, is it a network problem a client device problem.

Unfortunately, it seems it is not a Cloudflare issue and an end-user/device issue. Which requires more in-depth troubleshooting, which is not advisable to do over the internet from a security standpoint. For the next steps, I recommend that you see what certificate those users are trying to connect to because they could have a cache issue.