WebMailPRO automatically evaluates all incoming mail using K12USA’s advanced spam and content-filtering engines. When a message is delivered to your Junkmail folder—even though it appears legitimate—one or more rules likely triggered the system to treat it as suspicious.
This article explains all the possible reasons this may happen today and how your WebMailPRO administrator can whitelist safe senders or domains.
Possible Reasons Your Message Was Sent to Junkmail #
1. The message exceeded your account’s Spam Score threshold #
Your personal Junkmail settings may filter messages with a Spam Score of 6 or higher (recommended setting).
Even legitimate emails can accumulate points due to:
- Marketing-style formatting
- Images with little text
- Suspicious URLs
- DKIM/SPF/DMARC issues at the sender’s mail server
- Poor reputation of the sending IP or domain
2. The message triggered the Content Filter #
If the message contained phrases, attachments, or formatting commonly associated with spam, your Content Filter Score may have pushed it above the Junkmail threshold.
Common triggers include:
- Certain attachment types
- Embedded scripts
- Phishing-style content
- Obfuscated URLs
3. The sender’s email domain or IP has a poor reputation
Our filtering system uses multiple real-time reputation checks (RBLs, UriDNSBL, proprietary K12USA filters). Messages from senders with poor-reputation mail servers are more likely to be flagged.
4. The sender failed authentication checks
If SPF, DKIM, or DMARC fail, the message may be treated as untrusted.
This is extremely common with:
• Forwarded messages
• Third-party mail services
• Misconfigured mail servers
• Bulk-mail platforms (MailChimp, Constant Contact, etc.)
5. Organizational Global Mail Rules
Your WebMailPRO domain administrator may have global rules enabled for:
• Blocking mail from outside addresses except whitelisted domains
• Junkmail placement based on Spam or Content Filter score
• Delete-level thresholds
• Special handling of high-risk senders
(See “Admin Whitelisting Options” below.)
6. The sender is on your personal Block List
Users can accidentally block senders. This causes the message to bypass inbox delivery entirely.
7. Auto-classification due to past user behavior
If you frequently delete or mark similar messages as spam, filtering may adjust over time—even though it’s not a “learning” system in the same way as consumer mail services, patterns still matter.
________________________________________
How a WebMailPRO Administrator Can Whitelist a Sender or Domain
If you trust the sender, your WebMailPRO admin can whitelist them at the Global Mail Rules level so their messages bypass spam tests and/or content filtering.
Below are the updated WebMailPRO admin options (as shown in your screenshots).
________________________________________
Option 1: Allow Incoming Mail From Specific Outside Addresses
This bypasses the block-outside-senders restriction, but still tests for spam unless the admin chooses otherwise.
Path:
WebMailPRO → Manage Organization → Global Mail Rules → Outside Email Addresses
Allow incoming mail from these email addresses, but test them for spam and content
Allow incoming mail from these email addresses, but do not test for spam (less recommended)
Admins can click View/Edit the List to add:
• A full email address (e.g., sender@example.com)
• A domain (e.g., example.com)
________________________________________
Option 2: “Block No Incoming Email From Outside Except…” (Recommended)
Most schools use this stricter mode.
Admins can add approved senders/domains to the allow list, ensuring they always pass the outside-sender restriction.
________________________________________
Option 3: Whitelist for Spam/Content Filter Testing
Admins can prevent spam/content filtering for specific senders:
Do not Spam Test or Content Filter external incoming email from the following list:
→ View/Edit the List
This is helpful when:
• A sender has poor technical email configuration
• Important automated messages keep getting flagged
• Bulk mail (school messaging systems, HR systems, etc.) fails authentication checks
________________________________________
Option 4: Adjust Junkmail Rules
Admins can modify global Junkmail placement thresholds:
• Content Filter Score
• Spam Score
• Per-user or domain-wide settings
• Delete thresholds (messages deleted before reaching Junkmail)
If the thresholds are too low, legitimate mail may land in Junkmail.
________________________________________
If a User Is Not Receiving Any Email From a Particular Sender or Domain
If no messages from a domain arrive—not even in Junkmail—there may be:
• A hard block
• SPF/DKIM/DMARC failure
• Sender reputation issues
• RBL blockage
• Policy-based blocking
• Attachment-based blocking
Please contact us at:
support@k12usa.com
To help us diagnose quickly, please ask the sender to forward:
1. The bounce-back message they received
o This contains exact technical reasons for block/failure
o Example: RBL listing, SPF fail, attachment restriction, etc.
2. A new test message sent to:
o support@k12usa.com
o k12usa@gmail.com (for deeper filtering comparison)
We use the same filtering engine on both accounts, and receiving the message at both destinations lets us:
• Compare logs
• Identify rejection events
• Diagnose real-time mail flow issues
This greatly speeds up troubleshooting.
________________________________________
Need Assistance?
We’re always here to help.
If you continue to see legitimate mail delivered to Junkmail—or missing entirely—please contact:
support@k12usa.com
877-225-0100