Following error may occur when sending emails from domains with incorrect spf record.
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lnx01.abcd.com rejected your message to the following email addresses:
user@domain.com (user@domain.com)
A problem occurred while delivering this message to this email address. Try sending this message again. If the problem continues, please contact your helpdesk.
lnx01.abcd.com gave this error:
192.168.20.56 is not allowed to send mail from example.com. Please see http://www.openspf.net/Why?scope=mfrom;identity=user@example.com;ip=192.168.20.56
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If a domain hosted in bytehouse exchange is using spf record, then it should contain "include:spf.serverdata.net" and "a:mailers.bytehouse.co.uk". If domain is not using spf, then there is no need to add spf record
If domain contains spf record, you can add spf records in the following format.
Eg: "v=spf1 +a +mx a:mailers.bytehouse.co.uk include:spf.serverdata.net -all"
If you experience any issues or if you need assistance in adding the spf records, please contact Bytehouse Technical Support.