521 upstream error.
Hello! I have been using my email address for almost a year and now I can't receive any emails through with this error coming through - does anyone have a fix?
22 Replies
If you go to Email Routing -> Overview -> Activity log, what do you see there about the email?
Magic link: https://dash.cloudflare.com/?to=/:account/:zone/email/routing/overview
Just a long list of errors with emails not being received
You should be able to click and expand and potentially get some more info
Unknown error: permanent error (521): 5.3.0 Upstream error, please check https://developers.cloudflare.com/email-routing/postmaster for possible reasons why. 4VMNw1vgNMRt
Is the rejected reason
What's the destination you're forwarding it to? a gmail?
Its setup through the custom email feature with iCloud+ rather than Gmail
If you're using the custom email feature with ICloud, shouldn't be using Email routing
you're forwarding to an address on the same domain as its recieving on?
Okay, so would I just need to remove the email routing then?
you'd need to restore the records back to the icloud defaults
https://developers.cloudflare.com/support/more-dashboard-apps/cloudflare-registrar/icloud-custom-email-domains/ shows a screenshot of what they should look like, -- probably just have the wrong MX Records/need to recreate
iCloud Custom Email Domains · Cloudflare Support docs
With iCloud Custom Email Domain , you can now purchase a custom domain right from iCloud Settings through Cloudflare and have it automatically set up …
Thank you ! I will give this ago and see it it works
Hello! that has not worked
I still see Cloudflare's email routing MX records at
gardnerindustries.co.uk. In some cases, gmail/etc may cache the records for a bit as well, wouldn't expect it to work instantlyI have these at the top of the DNS records page now
So do I need to have anything set if I look in, Email routing - routes?
I'm just getting address does not exist now errors.
Your MX addresses are still unchanged
You need to disable email routing entirely, and replace the email routing MX records with the icloud ones in the screenshot of the guide. You also are lacking the spf record looks like, also in that guide
I have removed the custom address from email routes and I have deleted the destination email
that's not enough, when you enabled Email Routing it replaced your MX Records, which decide where mail goes to. Right now, mail is just going to Email routing still and broken.
To switch back to ICloud handling your email, you need to disable Email Routing and replace the MX Records
Shall I delete the current records and just create new ones?
The current MX Records pointing to Cloudflare, yea. You'll be unable to modify them unless you disable Email routing first though (under Email -> Email routing -> settings)
Okay I have done that, assuming I need to add the records shown in that link you sent?
yea the two MX records going to mx01 and mx02 icloud.
You should also have a txt record on your domain starting with
v=spf1, if you don't, copy that.
The DKIM one as well, which looks like it just needs to be same name, but content of sig1.dkim.<yourdomain>.at.icloudmailadmin.com, so sig1.dkim.gardnerindustries.co.uk.at.icloudmailadmin.com in your caseThank you very much! I will enter that and see what happens and come back to you
Hello! I made those changes and it seems to have resolved the issue 😀 thanks so much for your help!
Hello. Looks like I am not alone, but I am getting the following error:
Unknown error: permanent error (521): 5.3.0 Upstream error, please check https://developers.cloudflare.com/email-routing/postmaster for possible reasons why. Oi8dHH3nG3C2
Does anyone have experience with this?