Rather than manual invoice uploads to PredictAP, Microsoft 365 can automatically forward them to the Smart Invoice Inbox.
Key Steps & Requirements
Create a New Mailbox
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Set up a new user mailbox (not an alias).
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Assign it an Exchange license.
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Ensure invoices are received and sent from the same mailbox.
Avoid Aliases
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Aliases are not supported — use full licensed mailboxes only.
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Email forwarding from aliases can lead to delivery issues.
Check for Conflicts
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Review mailbox and global rules to ensure no existing rules interfere.
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Third party anti-spam policies may block forwarding — configure them accordingly.
Outlook/Microsoft 365 Setup (must have administrator access to set up contacts, creating forwarding rules, and enable outbound policies)
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Create the new user mailbox via Microsoft 365 Admin Center.
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Add PredictAP as a contact in Microsoft 365 Admin Center.
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Set up a mail flow rule to forward all emails to PredictAP.
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Enable outbound forwarding in Microsoft Defender anti-spam settings.
Click the title to be directly sent to the relevant section of this article. The below instructions will cover the following:
Create a New Outlook User Mailbox
Configure the Outlook Forwarding Rule
Enable Outbound Forwarding in Microsoft Defender
Microsoft 365 Invoice Forwarding
Configuring Microsoft 365 forwarding requires you to create a new user mailbox, configure an Outlook forwarding rule, and enable outbound forwarding at the administrative level.
Step 1: Create a New Outlook User Mailbox
The Microsoft Admin Center allows you to create user mailboxes in Microsoft 365.
How to Create a New Mailbox
- Navigate to the Microsoft 365 Admin Center using your administrative credentials.
- Click on Users - Active Users.
- Click on Add a user.
4. Type to complete the First name, Last name, Display name, and Username fields. 
5. Click on Next.
6. The Assign product licenses page appears. Select your country from the Select location drop-down menu.
7. Click Assign user to a product license, and then select the available license for the new mailbox user.
8. Under the Apps section, click on the All licenses drop-down menu. Click the checkbox to select Exchange Online and (optionally) any additional available licences you wish to associate with the new mailbox user.
9. Click on Next.
10. On the Optional settings page, click on Next.
11. Review the new user mailbox, and click on Finish adding.
Step 2: Add designated PredictAP Smart Inbox email address to Microsoft 365 as a Contact
1. Navigate to Microsoft 365 Admin Center
2. Select Contacts --> Add a Contact
3. Fill in:
First Name (ex: Predict), Last Name (ex: AP)
Display Name (ex: PredictAP)
Email address (ex: invoices@yourcompany.predictap.com)
Do not select 'hide from my organization's global address list'.
4. Select Add.
Step 3: Configure the Outlook Forwarding Rule
Use a new Outlook rule to forward all emails from your new mailbox to PredictAP.
How to Forward Outlook Emails
- In the Outlook web client, click your profile in the upper right corner and click the Open another mailbox link.
- Type in the address of the mailbox and then click Open. In this example, the inbox to be forwarded is invoices@companyname.com.
3. Ensure the inbox to be forwarded is active by reviewing the address in the browser. The email address should be included in the web address.
4. Click on the cog icon.
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- Specify a name for the Rule
- Select Apply to all messages from the condition dropdown
- Select Forward to from the action dropdown
- Enter the PredictAP Smart Inbox email address (ex: invoices@yourcompany.predictap.com) for your PredictAP environment. The email address should auto-populate to select since adding it as a contact in above steps.
- Contact PredictAP if you do not know the Smart Inbox email address.
6. Click Save
Important Note: Forwarding should not be used.
Enable Outbound Forwarding in Microsoft Defender
By default, Microsoft 365 Defender disables the ability to forward emails to another mailbox. The forwarding rule fails to result in a bounce-back email without enabling the Outbound Forwarding policy through the Microsoft outbound spam filter.
Before enabling outbound forwarding, consider the following:
- You must be an Exchange administrator or Global administrator in Microsoft 365.
- Only new emails sent to the mailbox are forwarded.
To Enable Outbound Forwarding in Microsoft 365 Defender
1. Navigate to the Anti-Spam Policies in Microsoft 365 Defender using your administrator credentials.
2. Click on Create Policy and Outbound from the drop-down menu. Please create a new policy, do not add mailbox to existing policy.
3. Type a Name and (optional) Description for the new outbound policy.
4. Click on Next.
5. Choose whether to add specific users (ex: invoices@yourcompany.com), groups, or domains for the outbound policy. For example, type and select a user if invoices are emailed to only one mailbox in the organization.
6. Click on Next.
7. Click on Automatic forwarding rules and select On - Forwarding enabled from the drop-down menu.
8. Click on Next.
9. Review the new outbound policy, and then click on Create. 
10. Click Done.
FAQs & Best Practices
Can I use an alias or shared mailbox instead of a full licensed mailbox?
No. Aliases and shared mailboxes are not recommended and can cause issues with delivery or source authentication. Please use a licensed user mailbox.
Why must invoices originate from the same mailbox they were received in?
PredictAP relies on the source mailbox address to validate and process forwarded invoices correctly. Using a different "send from" address can cause rejections and routing issues.
What licensing is required for the mailbox?
You'll need a Microsoft 365 license that include Exchange Online capabilities.
Are there any Microsoft Defender settings I need to change?
Yes. Microsoft Defender disables forwarding by default. You must enable outbound forwarding via a new policy in the Microsoft 365 Defender Admin Center.
What if emails are not being forwarded even thought the mailbox rule is set up?
Check that:
- The mailbox is licensed and active.
- PredictAP Smart Inbox was added as a contact first.
- Microsoft Defender outbound policy is enabled.
- No spam or mail flow rules are blocking the forwarding.
What is the PredictAP Smart Inbox address I should use?
Each customer has a unique Smart Inbox address, e.g., invoices@yourcompany.predictap.com. Please contact your designated CSM or Product Specialist if you're unsure what your forwarding address is.
What's the best way to configure a forwarding rule in Outlook?
- Use the Outlook Web App to log into the new mailbox.
- Set a rule to forward all emails to your PredictAP Smart Inbox.
- Ensure you've added PredictAP as a contact in your Microsoft 365 Admin Center beforehand.
Can I add PredictAP as a forwarding address without admin access?
No. You must have administrator access to set up contacts, creating forwarding rules, and enable outbound policies.
Can I set up multiple forwarding addresses for different departments or properties?
Yes. Many customers configure property-specific inboxes to forward into their PredictAP Smart Invoice Inbox,
What happens if I forget to enable outbound forwarding in Microsoft Defender?
The rule silently fails. Emails won't be forwarded, and there may be a no bounce back or visible failure alert - so enabling outbound forwarding is critical.
Do I need to inform my IT or security team about this configuration?
Yes. Your IT/security team should review any forwarding setup to ensure compliance with internal data policies and security protocols.
Can I use distribution lists to forward invoices?
No. These are not compatible with PredictAP's required forwarding set up.