Problems with sending to certain servers
Hello. In the last few weeks, when sending emails, I have increasingly received the automatic response “Mail Delivery Status Notification (Delay)” with the notes “The following addresses had fatal errors” and “Message will be retried for 4 more day(s)”. Only to receive the message “Undelivered Mail Returned to Sender” after a few days. With the error messages “A message that you sent could not be delivered to one or more of its recipients. This is a permanent error.” and “ERROR CODE :450 - 4.7.25 Client host rejected: cannot find your hostname.”
Among other things, I have problems with emails to the TLD "arcor.de" and "colter-gmbh.de". Receiving emails with these addresses is not a problem. It's all about sending. (And only from my Zoho address. It works perfectly with other email addresses (e.g. GMail).)
What's going on here? Why is that? How can this be fixed?
Deliver unforgettable customer experiences
Deliver unforgettable customer experiences
New to Zoho Marketing Plus?
Everything you need to run your marketing
New to Zoho Marketing Plus?
Everything you need to run your marketing
Zoho Desk Resources
-
Desk Community Learning Series
-
-
-
-
-
-
-
-
-
Sticky Posts
Open PGP integration with Zoho Mail is now here!
Hello Community, We're in much delight to announce that the long awaited integration of Open PGP with Zoho Mail is now released to users in US, EU, AU and IN DCs. With this integration. you can now send out encrypted and digitally signed emails which
Free Webinar Alert! Transform your digital work experience with Zoho Workplace and Zoho Sign
Hello Community!!! We're excited to announce the free webinar on Transforming your digital work experience with Zoho Workplace apps and Zoho Sign integration! Join us for the webinar! Click here, to register!
Announcing ZUG Australia & New Zealand Meet-ups - Meet, Talk, and Learn from Workplace Experts!
Hello Everyone! Our Workplace experts are visiting the top cities in Australia & New Zealand to meet you all in person and help you boost the productivity of your organisation. Come and meet us at one of the cities listed below - whichever is nearer to
Announcing ZUG New Zealand Meet-ups in Auckland, Wellington & Brisbane - Meet, Talk, and Learn from Workplace Experts!
Hello Everyone! Our Workplace experts are visiting the top cities in New Zealand to meet you all in person and help you boost the productivity of your organisation. Come and meet us at Auckland, Wellington or Christchurch - whichever is nearer to you.
Announcing ZUG Australia Meet-ups in Melbourne, Sydney & Brisbane - Meet, Talk, and Learn from Workplace Experts!
Hello Everyone! Our Workplace experts are visiting the top cities in Australia to meet you all in person and help you boost the productivity of your organisation. Come and meet us at Melbourne, Sydney or Brisbane - whichever is nearer to you. Find our
Zoho TeamInbox Resources
Zoho DataPrep Resources
Zoho CRM Plus Resources
Zoho Books Resources
Zoho Subscriptions Resources
Zoho Projects Resources
Zoho Sprints Resources
Qntrl Resources
Zoho Creator Resources
Zoho WorkDrive Resources
Zoho Campaigns Resources
Zoho CRM Resources
Zoho Show Resources
Writer Get Started. Write Away!
Writer is a powerful online word processor, designed for collaborative work.