‘SPF validation unavailable’ means there’s a problem with your domain’s SPF record. You can run your SPF TXT record through an SPF check tool that will diagnose it in a few steps and highlight information on all the existing issues. There are a number of reasons causing an SPF validation unavailable error; some common ones are-
- Misconfigurations in your SPF DNS record.
- Wrong use of syntax (mechanism, qualifier, and modifier)
- Use of mx and ptr mechanisms.
- Not adding IP addresses or mail servers of all the senders. Example: third-party vendors who send emails on your behalf.
- Exceeding the limit of DNS lookups.
Erroneous SPF records impact email deliverability and impede DKIM and DMARC operations in one way or the other.
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Types of Errors Causing an SPF Validation Unavailable Issue
Pass
The sender is officially authorized to send email messages on behalf of your company and using that particular domain name.
None
The server wasn’t able to locate an SPF record for your domain. In this case, you need to confirm if your domain’s SPF record exists and is published on the DNS.
Neutral
It doesn’t explicitly indicate if a specific IP address or mail server is allowed to send an email message representing your organization. It’s represented by the ’?all’ tag and is almost equal to a missing SPF record.
Temperror
It’s a temporary SPF validation error that’s most likely to arise due to a momentary issue like a DNS timeout or server unavailability. Domain owners shouldn’t be too concerned about this error unless it occurs frequently. If it gets too regular, they need to check their SPF records and seek help to remediate highlighted problems immediately.
Permerror
You will receive an SPF permerror notification if a recipient mail server (Gmail, Microsoft Exchange Office 365, Hotmail, etc.) fails to check your SPF record correctly. It indicates the existence of a syntax mistake or misconfiguration.
Softfail
The sender’s IP address isn’t listed in the SPF record, which means they are not officially authorized to send emails representing your business. A softfail (indicated by the ~all tag) instructs mailboxes of recipients to be wary of such senders and places emails sent by them in the spam folder.
Fail
It’s represented by the ‘-all’ tag and instructs a receiver’s SMTP server to reject the entry of any illegitimate email coming from your domain. It’s used to abort the attempts of malicious users who plan phishing, spoofing, or spam attacks by exploiting reputed businesses’ domain names.