Here’s a list of the different types of the Return Path Platform's Smart Alerts feature, including the issues that trigger them: 

• DKIM: There are 14 components this alert checks for: 
• DKIM Error: Neutral (no sig) or Neutral (unknown) (likely causing issues at all MBPs): This checks whether or not you have a DKIM signature set up.
• DKIM Error: Neutral (no sig) or Neutral (unknown) (likely causing issues at some MBPs): This checks whether or not you are a missing a DKIM signature at any of the mailbox providers you send to.
• DKIM Error: Temperror and no TXT record: This checks whether or not you have a published DNS TXT record for DKIM.
• DKIM Error: Temperror and TXT record: This checks whether or not your DKIM public key was published.
• DKIM Error: Temperror and public key published: This checks whether or not your DKIM public key matches your private key.
• DKIM Error: Temperror (multiple keys): This determines if you have too many published DKIM keys.
• DKIM Error: Policy (weak key): This checks if your DKIM key length is too short.
• DKIM Error: permerror (length tag error): This checks if your DKIM length tag is correct.
• DKIM Error: Permerror (future timestamp): This checks if your DKIM timestamp tag is correct.
• DKIM Error: Permerror (invalid domain): This finds syntax errors in your DKIM signature.
• DKIM Error: Fail (unknown key version): This indicates that your DKIM public key version tag in the DNS record for your domain is set to an invalid value.
• DKIM Error: Fail (unknown key type): This indicates your DKIM public key type is set up incorrectly.
• DKIM Error: Permerror (no key): This indicates that the mailbox provider could not retrieve the public key in order to verify DKIM. 
• DKIM Error: Permerror (bad sig): This indicates potential various issues with DKIM such as DKIM configuration, DNS record, or the mailbox provider.
• DMARC: This checks whether or not you have a DMARC record set up.
• rDNS: This checks whether or not your IP address is connected to an authentic domain name.
• SPF: There are 7 components of the SPF check that let you know about various SPF issues:
• SPF: no record found: This checks whether or not you have an SPF record.
• SPF: IP(s) missing from SPF record: This checks if you have an SPF record set up but it is missing IPs.
• SPF: ?all/+all mechanism used: This indicates that you used the improper SPF record mechanism.
• SPF: Exceeded DNS lookup limit: This checks if you exceeded the limit of 10 DNS lookups during an SPF check.
• SPF: Syntax issue: This tells you that you have a syntax error in your SPF record.
• SPF: Exceeds character limit: This tells you that your SPF record exceeded the 255 character limit.
• URL Shorteners: This checks your message for link shorteners. Mailbox providers block email that appears to hide a sender's identity, and link shorteners hide where the link goes. This can make an email's content more suspicious. 
• List-Unsubscribe Header: This checks whether or not you have a List-Unsubscribe header in your email. This header gives your subscribers an easy way to unsubscribe, which reduces complaint rates. 
• IP Address: There are two components this alert checks for:
• Shared IP: This checks to see if you are sending from a shared IP address that could be having a negative impact on your deliverability rates. 
• New IP: This checks to see if you are sending from a new IP address that doesn't have an established sending history, which could be an issue with mailbox providers. 
• HELO: This checks your infrastructure for HELO.
• Open Relay: This checks to see if you have an improperly configured SMTP server that has an open relay.
• MX Record: This checks to see if the domain in your From header has an MX record listed in DNS. If you don’t have an MX record setup, you are unable to accept incoming email messages.
• Cloudmark: There are 8 components this alert checks for:
  • Attachments: This indicates that an attachment in one or more of your campaigns was flagged as a potentially harmful file type, generating a spammy Cloudmark fingerprint.
  • Email content: This indicates that the message content of one or more of your campaigns looks similar to campaigns reported as spammy by recipients, generating a spammy Cloudmark fingerprint.
  • Header/body: This indicates that the message header or body of one or more of your campaigns contains elements similar to campaigns reported as spammy by recipients, generating a spammy Cloudmark fingerprint.
  • IP reputation: This indicates that one or more campaigns received from this IP were reported as spammy by recipients, generating a spammy Cloudmark fingerprint.
  • Image: This indicates that one or more of your campaigns contains an image that has been reported as spammy by recipients, generating a spammy Cloudmark fingerprint.
  • Redirects: This indicates that one or more of your campaigns contains a URL redirect that was reported as spammy by recipients, generating a spammy Cloudmark fingerprint.
  • URL: This indicates that one or more of your campaigns contains a URL that was reported as spammy by recipients, generating a spammy Cloudmark fingerprint.
  • Multiple issues: This indicates that one or more of your campaigns contains multiple issues, generating a spammy Cloudmark fingerprint.