AegisAI Perspectives · 087
Stop real invoices being quarantined by reading the verdict, releasing with an admin submission and allowing one sender address for no more than 30 days.
Stop real invoices being quarantined by email security: release each held invoice with an admin submission, allow only the exact sender address for 30 days at most4, and never allow a whole domain. AegisAI reads each email through the Microsoft 365 or Google Workspace API after delivery and states the reason for every verdict23. Confirm any change to bank details on a second channel before anyone pays17.
Start with the X-Forefront-Antispam-Report header and finish with the narrowest expiring exception that the verdict allows.
In Microsoft 365, open the X-Forefront-Antispam-Report header of the held invoice: CAT:HSPM means high confidence spam, which goes to quarantine by default1. A value of BCL:7 to BCL:9 means the default bulk threshold of 7 caught it. Write the CAT and BCL values in the ticket, because each verdict has a different override.
Malware and high confidence phishing are always quarantined, whatever allowlist you use8. Recipients cannot release those messages and can only request release10. Route those requests to an admin, never to the accounts payable clerk.
In Microsoft 365, release the invoice from quarantine and submit it to Microsoft for analysis in the same action. Release similar held invoices by hand, because quarantine never releases them automatically. In Google Workspace, go to Apps > Google Workspace > Gmail > Manage quarantines, select the message, then choose Allow; the action cannot be undone12.
Compare the bank details on the released invoice with the supplier record, and confirm any change by calling a number already on file, since the FBI advises a secondary channel for account changes. IC3 counted 305,033 business email compromise incidents and $55,499,915,582 in exposed losses from October 2013 to December 202316, and how to prevent business email compromise sets out the payment controls around this call.
In the Tenant Allow/Block List, set Remove allow entry after to 1 day, 7 days or a date up to 30 days out. Left at the default, an address or domain entry stays until 45 days after its last use. The entry overrides bulk, spam, high confidence spam and phishing verdicts only5. For malware or high confidence phishing, submit the message as I've confirmed it's clean and select Allow this message.
A Tenant Allow/Block List entry cannot clear a user or domain impersonation verdict, so add the supplier to Trusted senders and domains in the anti-phishing policy that flagged it6.
Add the billing address to an address list, select that list under Bypass spam filters for messages from senders or domains in selected lists, and allow up to 24 hours for the change14. Require sender authentication for every approved sender, and keep domains off the approved list, because mail from an approved domain is not filtered for spam13. If suppliers send password-protected PDFs, check Protect against encrypted attachments from untrusted senders: set to Quarantine, it sends each one to admin quarantine15.
A PDF with embedded code or links to suspicious domains is flagged even when the invoice is real, and PDFs over 10MB often get blocked19. Send the supplier the checks in why email security false positives happen and how to fix the root cause, starting with the SPF and DKIM records that DMARC checks.
If you still need an Exchange mail flow rule that skips spam filtering, add a condition that the Authentication-Results header includes dmarc=pass, and never use the sender domain alone. Keep any IP Allow List range at /24 or smaller.
Match the setting to the verdict, then scope it to one sender address with an end date of 30 days or less.
| Setting | Where it lives | What it does | The risk if set too wide |
|---|---|---|---|
| Admin release with submission | Microsoft 365 quarantine, admin view | Delivers the held invoice and sends it to Microsoft for analysis | Similar invoices stay held until an admin releases each one |
| Allow entry for an email address or domain | Microsoft 365 Tenant Allow/Block List | Overrides bulk, spam, high confidence spam and phishing verdicts | A domain entry covers every address in that domain and, by default, lasts until 45 days after last use |
| Trusted senders and domains | Microsoft 365 anti-phishing policy | Clears a wrong user or domain impersonation verdict | A trusted domain is exempt from impersonation checks for every mailbox the policy covers |
| Mail flow rule that skips spam filtering | Exchange admin center, mail flow rules | Delivers matching mail without spam filtering | With the sender domain as the only condition, spoofed mail from that domain skips filtering |
| IP Allow List | Microsoft 365 connection filter policy | Skips filtering for mail from listed IP addresses | A range wider than /24 trusts addresses the supplier does not control |
| Approved senders list | Google Workspace Gmail spam settings | Bypasses spam filters for senders in the selected address lists | A domain on the list is not filtered for spam, which raises spoofing risk |
| Encrypted attachment protection | Google Workspace advanced phishing and malware settings | Keeps, moves to spam or quarantines password-protected attachments | Set to Quarantine, every encrypted invoice waits in admin quarantine |
| Quarantine retention | Microsoft 365 anti-spam policy | Holds spam, phishing or bulk mail 15 days by default, configurable from 1 to 30 days9 | A 1 day setting deletes an unreviewed invoice permanently |
A header check and a 30 day allow entry for one address clear the held invoice; a call to a known number clears the payment.
Illustrative example, figures are fictional. Fernhill Supply (fictional) has 120 staff on Microsoft 365 and one shared accounts payable mailbox. A packaging supplier's real invoice for $18,400 sits in quarantine for 9 days until the supplier chases payment. The admin reads the header: BCL:8, over the default bulk threshold of 7, because the supplier now sends invoices from a billing platform. She releases it with a submission to Microsoft and finds 3 more held invoices from the same address, which she releases by hand. She adds a Tenant Allow/Block List entry for that one billing address, set to end after 30 days. The clerk finds the bank details match the supplier record and still calls the number on file, because this is the first invoice from the new platform. The supplier confirms by phone, and Fernhill pays 2 days later. With 6 days left of the 15 day default hold, no invoice expired.
AegisAI reads mail through the Microsoft 365 or Google Workspace API after delivery. Every verdict comes with its reason in plain language, so your team can check it and share it22. Graymail and spam are sorted out of the inbox, and quarantine is kept for threats24. The median verdict takes 1.9 seconds, and a convicted message is removed from every mailbox it reached within seconds21.
Track three numbers for the accounts payable mailbox each week, starting the day you add the first Tenant Allow/Block List or approved senders entry.
To compare those three numbers with an API-based second reader on your own tenant, use the AegisAI demo page.
Read the verdict in the header, release the invoice as an admin with a submission, and allow only the supplier's exact address with an end date of 30 days or less. Fix the cause with the supplier, and confirm bank detail changes on a known phone number before paying.
Avoid it. Google says not to add domains to the approved senders list, because mail from those domains is not filtered for spam. Microsoft says a mail flow rule should never skip spam filtering on the sender domain alone, and should check for dmarc=pass.
Recipients cannot release messages quarantined as malware or high confidence phishing; they can only request release. An admin submits the message as I've confirmed it's clean and selects Allow this message, because a direct allow entry does not override those verdicts.
In Microsoft 365, spam, phishing and bulk messages stay 15 days by default, or 30 days under the Standard and Strict preset policies, and expired messages are permanently deleted. In Google Workspace, denied messages are deleted 30 days after they were sent.
By default, an allow entry for an address or domain stays until 45 days after its last use. You can instead set it to end after 1 day, 7 days or on a date up to 30 days away.
Gmail spam setting changes can take up to 24 hours to take effect. The bypass setting also does nothing until you select at least one address list.
