Using classic Outlook for Windows in business environments
I have just started having the same issue. I see that the others have been experiencing this since 2022! Why isn't there any solution since then?
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Hi
I am using outlook 2021, recently many of my emails rejected, and I am getting the below massage regardless to whom i sending to (some pass without any issue)
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This message was created automatically by mail delivery software.
A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:
**information removed due to privacy policy**
message has lines too long for transport
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report shows
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X-Mailer: Microsoft Outlook 16.0
Thread-Index: **information removed due to privacy policy**
Content-Language: ar-jo
X-Exim-DSN-Information: Due to administrative limits only headers are returned
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Using classic Outlook for Windows in business environments
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I have just started having the same issue. I see that the others have been experiencing this since 2022! Why isn't there any solution since then?
This is issue with cPanel / WHM - Settings. Your cPanel hosting Vendor needs to fix in EXIM settings.
nothing to blame Microsoft. (We have lot of ther ways to blame Microsoft - like mximum PST OST limit 50GB, etc 😃 )
Hi Mohamed, please could you give us more information on the steps/technical on this based on what you know? Most of us are novices and need to be able to approach our hosting provider with the right information to solve our problem.
You may be our saviour on this issue, so appreciate your help!
Hi,
Please follow this screenshot https://drive.google.com/file/d/1c1ufsHjdKnuyOW70BdaYTsm9bKwNSq5l/view?usp=drivesdk - Configuration to be done in cPanel WHM
Explanation:
Any email with a header will increase in length every time the user replies or forwards the same mail.
When sending emails via SMTP from Outlook, these headers need to be processed properly according to the value set in cPanel EXIM. If cPanel EXIM is configured with a header size limit smaller than 2048 bytes, outgoing emails will result in an error message. The solution is to increase the header size limit, as shown in the above screenshot.
Unfortunately, hosting companies often refuse to make this change, citing reasons such as "this is not possible" or "we cannot do this on shared hosting."
To resolve this, I created my own cPanel/WHM VPS server to have full control and apply this fix.
Quick fixes if your hosting provider doesn't respond:
If your hosting provider has made the required changes and your problem is resolved, please mention the provider's name here.
Good luck!
Thanks, I've lodged the ticket with my host (Heart Internet), will let everyone know how it goes.