I have the same problem on my site.
When cloudflare is active, I can not send e-mails.
When CloudFlare disabling, mail was sent.
Please open a ticket - Tech support will look into the issue and the relation with to Cloudflare.
Hello,
Thank you for your clarification.
We can see that webmail.xumaru.com does resolve to our IP correctly.
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C:\>ping webmail.xumaru.com
Pinging webmail.xumaru.com [70.32.28.69] with 32 bytes of data:
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You can even try to use 70.32.28.69 as the SMTP host instead as well to see if that helps in anyway.
We have even checked nopcommerce forums and cloudflare articles which does not point to anything specific. However, since it works without CloudFlare, it is clear that it is not our server-side issue and just a DNS issue with CloudFlare.
Can you see if changing the SMTP host to our server IP provided or the server name mi3-wss7.a2hosting.com resolves the issue?
On another important note, the below mentioned path does not actually exists.
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Error 404. The requested page (/scheduletask/runtask) was not found
The remote server returned an error: (404) Not Found.
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It’s a valid error as well. Could be some setting in your nopcommerce application somewhere.
If you have any further questions or need additional assistance, please do let us know.