Plugin
Updated
Office 365 Headers Removal
Office 365 Headers Removal is an add-on for the Newsletter plugin for WordPress, made by The Newsletter Team. It removes unwanted headers that Office 365 adds to outgoing newsletters, which helps avoid rejections and spam filtering caused by incompatible header information.
Install this firstPlease install the Newsletter core Plugin from here before installing the addons
Go to product- Version
- 1.0.7
- Released
- Aug 30, 2026
- Developer
- Newsletter
- Type
- WordPress plugin
- Licence
- GPL
- Included in
- Every plan, or $0.79 a year on its own
What’s new in Office 365 Headers Removal 1.0.7
Version 1.0.7
Latest
- ImprovedWP 7.1 check
What it does
When you send newsletters through Microsoft's email service, Office 365 can add header information that other mail systems do not handle well. That can lead to emails being rejected or caught by spam filters. This add-on targets that specific problem. It strips the unnecessary Office 365 headers from your outgoing messages so they follow stricter formatting requirements and arrive with a clean appearance.
The add-on works alongside the Newsletter plugin, so you keep building campaigns, managing subscribers and running automations the way you already do. There is no complicated setup. Once it is running, it works in the background and handles headers automatically each time emails are dispatched. It also keeps filtering headers when you send through the external SMTP services that Newsletter integrates with, and it applies to scheduled sends and autoresponder follow-ups as well.
Best for
- WordPress sites sending newsletters through Office 365
- Businesses running large Newsletter plugin campaigns
- Bloggers and marketers facing Microsoft-related delivery rejections
Features
Automatic header stripping
Removes the unnecessary headers Office 365 adds to outgoing newsletters, without you having to edit messages or adjust settings for each campaign.
Fewer rejections and spam flags
Proper header formatting reduces the chance that receiving servers reject your newsletters or filter them as spam because of incompatible header information.
Built for the Newsletter plugin
Works as an extension of the Newsletter plugin for WordPress, so your existing campaign creation and subscriber management workflow stays the same.
Works with external SMTP services
Keeps header filtering in place across the mail delivery services integrated with Newsletter, regardless of which sending method your site uses.
Runs in the background
Needs no complicated setup. It quietly manages headers during email dispatch, so you can focus on writing content instead of technical details.
Covers automation and autoresponders
Applies to messages sent through Newsletter's scheduling and follow-up features, so automated communication flows get the same header cleanup as regular campaigns.
Suited to large campaigns
Handles header cleanup consistently for sites sending high-volume newsletters through Office 365, keeping every message in a send formatted the same way.
Office 365 Headers Removal older versions
- 1.0.6Jul 17, 20241 improvement
- 1.0.5Jun 1, 20231 improvement
- 1.0.4Apr 18, 20231 improvement
Members and buyers of this product can download older versions.
Questions about Office 365 Headers Removal
Do I need the Newsletter plugin to use this add-on?
Yes. This is an extension for the Newsletter plugin for WordPress. It hooks into the emails Newsletter sends and removes unwanted Office 365 headers from them, so it relies on Newsletter being in place to do its job.
What problem does removing Office 365 headers actually solve?
Office 365 can add header information that some receiving mail systems treat as incompatible. That can cause newsletters to be rejected or sent to spam. Stripping those headers keeps your messages properly formatted so they are less likely to run into those issues.
Will it still work if I send through an SMTP service?
Yes. The add-on supports the major mail delivery services integrated with Newsletter and keeps filtering headers no matter which sending method you use, so switching delivery services does not turn off the cleanup.
Does it apply to automated emails and autoresponders?
It does. The add-on works with Newsletter's scheduling and follow-up features, so headers are removed from automated sends and autoresponder messages in the same way as regular campaigns.
Is Office 365 Headers Removal free?
The code of Office 365 Headers Removal is licensed under the GPL, so anyone may use, change and share it. GPL Feast is a paid service: a plan or a single purchase gives you the download and automatic updates. The developer's own support, licence key and online services are not included.
Which version of Office 365 Headers Removal is this?
Version 1.0.7, released Aug 30, 2026. New versions appear here when the developer publishes them, and members get them as automatic updates.
How do I update Office 365 Headers Removal?
Install the free GPL Feast Updater on your site and connect it with your API key. It installs new versions of Office 365 Headers Removal automatically and keeps a backup, so you can roll back.
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