Rebrand New harmon.ie
If your organization requires it, you may rebrand New harmon.ie to use your company’s logo, icons, links and labels. This is done by creating an Outlook add-in manifest file and hosting the required branding files on your CDN.
Before you begin
Prepare the following:
- Download and extract harmon.ie’s sample manifest file.
- Generate a unique add-in ID. Use any online UUID generator or run
uuidgenfrom Command Prompt or PowerShell. - A public HTTPS CDN for hosting branding files.
- Brand icons in the required sizes.
Step 1: Create the branding resources
A. Create resources.zip
The app downloads a file named resources.zip from the root of your branding CDN at startup, and uses it to replace display texts and URLs in the app.
Create a ZIP file named resources.zip that contains a single file named branding.json. Place branding.json at the root of the ZIP file, not inside a subfolder.
Use branding.json to override display texts and URLs in the app. All fields are optional, if they are not defined, the harmon.ie default values are used.
| Field | Default value | Description |
|---|---|---|
companyName |
harmon.ie |
Replaces visible occurrences of company name |
productName |
New harmon.ie |
Replaces visible occurrences of product name |
whatsNewUrl |
https://harmon.ie/documentation/sharepoint/new/whatsnew |
Link to a What’s new guide |
supportUrl |
https://harmon.ie/support/ |
Link to Get support |
trainingUrl |
https://harmon.ie/training/ |
Link to Training videos |
Example branding.json:
{
"companyName": "harmon.ie",
"productName": "New harmon.ie",
"whatsNewUrl": "https://harmon.ie/documentation/sharepoint/new/whatsnew",
"supportUrl": "https://harmon.ie/support/",
"trainingUrl": "https://harmon.ie/training/"
}
Email addresses such as support@harmon.ie are not changed by these overrides.
B. Prepare branding images
Make sure you have all required branding images according to this table:
| Image name | Image size in pixels |
|---|---|
| icon-16.png | 16*16 |
| icon-32.png | 32*32 |
| icon-64.png | 64*64 |
| icon-80.png | 80*80 |
| icon-128.png | 128*128 |
Step 2: Host the branding files on your CDN
Host the files you prepared in step 1 under the root of your branding CDN:
https://company-domain/assets/icon-16.pnghttps://company-domain/assets/icon-32.pnghttps://company-domain/assets/icon-64.pnghttps://company-domain/assets/icon-80.pnghttps://company-domain/assets/icon-128.pnghttps://company-domain/resources.zip
- Replace “https://company-domain” with your organization’s CDN URL.
- Make sure all files are publicly accessible over HTTPS.
Step 3: Update the manifest file
Update the downloaded manifest.outlook.branding.xml file as follows:
A. Replace the app ID
Each branded deployment must use its own unique add-in ID so it can coexist with other installations without conflict.
Replace the existing <Id> value with your created UUID.
B. Update the display texts
Replace the text in the following fields with the correct branded values.
| Field | What to enter |
|---|---|
ProviderName |
Your company name |
DisplayName |
The name you want to use for the add-in in Outlook |
Description |
App description. Shown when viewing the app in Apps. |
TaskpaneButton.Label |
The label you want to show on the ribbon button |
TaskpaneButton.Tooltip |
App tooltip. Displayed when hovering over the app icon in the message toolbar. |
Example:
<ProviderName>harmon.ie</ProviderName>
<DisplayName DefaultValue="New harmon.ie"/>
<bt:String id="TaskpaneButton.Label" DefaultValue="New harmon.ie"/>
C: Update resource URLs
Replace every https://company-domain placeholder in the manifest with the HTTPS root URL of your branding CDN.
Update these locations in the manifest:
- Image URLs – update
IconUrl,HighResolutionIconUrl, and allbt:Imageentries to point to your branded icon files. - Taskpane URL – update the
brandingUrlquery parameter in<bt:Url id="Taskpane.Url">so it points to your CDN root URL. - AppDomains – add or update your CDN domain in the
<AppDomains>section so Outlook trusts content loaded from it.
Step 4: Enable CORS on your CDN
The taskpane is hosted on https://app.harmon.ie and loads branding files from your CDN by using browser requests (fetch()).
Configure your CDN to return the following HTTP response headers for all branding files under /assets/ and for resources.zip:
Access-Control-Allow-Origin: https://app.harmon.ie
Access-Control-Allow-Methods: GET, HEAD
Validate the branded deployment
Before distributing the branded manifest, verify the following:
- The manifest contains a new unique add-in ID.
- The display values have been updated.
- All icon URLs use HTTPS and return the correct files.
- The
brandingUrlparameter points to the correct CDN root. - The branding CDN domain is listed in
<AppDomains>. resources.zipis publicly accessible.resources.zipcontains a validbranding.jsonfile.- CORS is enabled for
https://app.harmon.ie.




