An error occurred requesting list information from Mailchimp.

Based on a web search of this phrase, this is an issue on the Mailchimp end of things and isn't related to the module.

@xenophyle I don't really agree. The API was used via the module and we did nothing special. Maybe the module simply sends too many requests and should better combine them in a timeframe or something like that?

I'd vote to reopen this.

Hey there — this is a tricky one. We have seen it a couple of times (well, once → that I know of) over the years we've been maintaining the Mailchimp suite, but we've never successfully pinned down what causes it. I am encouraged that it has only made it to the issue queue that one time, but of course I'm sure that's no consolation for you.

To try and make more progress with it, let's get all the info we can.

• Can you paste here the entire error message you're seeing (including all HTML)?
• Did the problem definitively start at a certain point (e.g. after upgrading to a certain version of the module)?
• If you're not already using OAuth rather than an API key to authenticate, can you try that (admittedly, a shot in the dark)?

Hey @anybody — just wanted to check on this. Should we assume the problem cleared up with a recent release, or...?

Just cropped up for me over the last couple days after working fine for years, and I'm using OAuth to authenticate.

It's hit and miss though -- on a page/function accessing the Mailchimp API, sometimes it will throw the "suspicious IP" error but reloading the page/re-sending the request it will work.

For example on the OAuth settings page I re-authenticated and have a "Authentication complete! Successfully connected to Mailchimp API" on that page... but if I reload the page... then I might see "Error, please re-authenticate" but if I reload the page once or twice it'll be happy again.

Possibly related, the website in question is hosted on Pantheon which uses dynamic IPs for outgoing requests. I'm guessing a Pantheon-hosted site was doing something that got that IP flagged by a database of suspicious IPs that Mailchimp relies on.

In short... I don't think this is a module issue but a problem with dynamic outgoing IPs on shared hosting. I see Pantheon has instructions for setting up a fixed-ip proxy for outgoing requests, I might have to look into that.

Updating this because I’m experiencing the same issue and might worth documenting it.

We've been using the API for years, but recently got flagged by Mailchimp's Akamai and our IP was blocked.

After a long conversation with Mailchimp support, their response was essentially: "We can’t tell you why this happened, and the only solution is to change your IP address, since we can’t unblock it on our side."

This makes things quite difficult. I’m hosted on Platform.sh, which, from what I can tell, uses a limited pool of outbound IPs—this could be a real issue in such cases.

The only workaround I can think of is to use a proxy between my site and Mailchimp. I’ve noticed some proxy-related configuration options in the module, but I haven’t figured out how to use them yet.

I'd also suggest adding a mechanism to limit or count API calls over a given time period, to prevent the module from overwhelming Mailchimp with requests. On one of my pages, I noticed several API calls being triggered, and with thousands of users, this could quickly become a problem.

Thanks for this, @kiwad and @derekw. I'm bugging Mailchimp's tech folks for some inside info about this now and will report back with what I learn.

Ok @kiwad, got a quicker-than-expected response. Mailchimp's tech folks say:

ok yes this is Akamai. SO if you can get me a reference number, which is included in most of these api responses that are blocked, i can look up exactly what akamai says about their IP. This typically occurs on SHARED HOSTING because someone on the shared server has a bad IP and akamai blocks the server. Akamai is our tool for protecting MC from ddos attacks and other malicious traffic. It is a little black box and mysterious so I cant promise I'll be able to do much for these users. But if they are on their own servers, not shared hosting, and experiencing these problems, Akamai might be flagging them for some reason.

as integration maintainers you cant do much except pass us the reference numbers as they come in and I can do my best to see if i can find anything out. the reference numbers only live for about a day so its gotta be kinda quick

Because you just wrote, @kiwad, I have some hope that the reference number might still be in your watchdog record, and that it's still "alive" per the above. Got it handy?

@bdimaggio

I do have many of those ref Numbers >Reference Number: 00.0b933617.1753379264.1a0818b5

I’ve checked with platform.sh and i’m stucked with limited outbound IPs, meaning that I either use a proxy or move away from Mailchimp

I’m guessing anyone with shared IP might be in same problematic situation eventually

Hey @kiwad — yeah, that's a big pain... and doesn't leave you a lot of real options. I've spoken to my higher-up tech contact at Mailchimp about this; he's very apologetic and he acknowledges that it's a problem, generally. As for your specific case, that ref # timed out, since they only "live" for a day.

Since I won't be online for a lot longer today, let's do this: starting Monday, if/when the problem recurs, DM me immediately with the ref number and I'll pass it on to my contact. At least we should be able to get more information that way.

@bdimaggio

Thanks for the follow-up. My IP had been blocked for approximately 72 hours, but the service is now restored.

This incident highlighted a potential point of failure in my current setup, so it wasn’t entirely a loss—it gave me perspective.

That said, the fact that Mailchimp claims they cannot unblock an IP and have no control over the situation is, to me, quite concerning from a service reliability standpoint.

Since my setup doesn’t allow me to change the outbound IP and I can’t reasonably advocate for an unblock with my provider, I’m considering developing a custom module that would:

Ping Mailchimp (periodically via cron or a through a hook/event triggered by the Mailchimp module).
If the response indicates the IP is blocked, automatically send me an alert email and route further requests through a proxy.

I was going to mark the issue as “Works as Designed,” but I see it’s already in that state.