An Office service that supports add-ins to interact with objects in Office client applications.
1,152 questions with Microsoft 365 and Office | Development | Office JavaScript API tags
How to turn off - Tracking Prevention blocked access to storage for https://appsforoffice.microsoft.com/lib/beta/hosted/office.js.
The following message started appearing recently. Tracking Prevention blocked access to storage for https://appsforoffice.microsoft.com/lib/beta/hosted/office.js. This appears when I launch a word add-in . Is it possible that this is a side affect of a…
Microsoft 365 and Office | Development | Office JavaScript API
Office.context.mailbox.item returns empty object when translateExchangeIds fails with 403c
We're experiencing an intermittent issue in our Outlook add-in, ExtendSync for Outlook by CloudExtend. We read the selected mail item via Office.context.mailbox.item, use convertToRestId() to get the REST ID, and call makeEwsRequestAsync() for additional…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Why the add-in no longer has access to the sent item for further processing or modification
I have created Outlook add-in using Office.js and noticed that after the ItemSend event completes, the add-in no longer has access to the sent item for further processing or modification. This limits scenarios like post-send tagging, content updates, or…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
How do I migrate my add-in to use the Graph-based getCallbackTokenAsync to bypass these legacy EWS blocks while maintaining shared mailbox support?
"403 Forbidden" when my add-in attempts to call makeEwsRequestAsync on mailboxes tagged with the new 2026 "Restricted Access" policy. Even though the add-in manifest has ReadWriteMailbox permissions, the backend is rejecting the…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Document.insertHtml failing with Error 5001 in 2026 Enterprise builds
my Word add-in tries to inject complex HTML fragments into a document containing legacy track changes and got Error 5001
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
"Manifest validation failed" in M365 Admin Center
I encounter the error "Manifest validation failed" in the M365 Admin Center while attempting to update our internal Outlook add-in. Even though the file passes office-addin-manifest validate with zero errors on my local machine, the…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
getAccessToken failing for sideloaded Outlook Add-In, then working, then failing again
An Outlook Add-In that was working since at least November 2025 failed to load earlier this week. No changes have been made in the meantime to the code or Entra settings. It turns out that Office.auth.getAccessToken was throwing OSF.DDA.Error with …
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Using a dynamic HTML script for my email signature
Hi I want to add a dynamic HTML script for my company's email signature on outlook. It needs to be enforced to all my employees in my M365 directory and it needs to be able to read their name, role, and email address to provide them as hyperlinks in the…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Access Denied Error (3399614466) When Acquiring NAA Token in Outlook Add-in
Issue Description: We are imlementing sso in Outlook Add-in using Nested App Authentication (NAA) with MSAL.js (createNestablePublicClientApplication). When calling acquireTokenPopup(). I have taken all references from here…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Word.ContentControl.insertFileFromBase64 does not replace Date Picker Content Controls in document headers.
Product: Office.js Word Add-in (Word on the Web / Word Desktop) API used: Word.ContentControl.insertFileFromBase64() / Word.Range.insertFileFromBase64()** Scenario:** I am building a Word Web Add-in that programmatically replaces document content…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
How can I optimize the Excel.run batching logic to ensure proxy objects are properly garbage collected between sync cycles?
Our Excel Add-in is consistently crashing during large data exports because context.sync() isn't releasing proxy objects fast enough, leading to massive memory leaks in the Office JS runtime. Even when I break the updates into smaller batches, the…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
MS Word Add-in : How to fetch the logged-in user details in typescrpit
Hi Team, We are developing new MS Word Add-in. We have requirement to fetch the current logged-in user details (mainly email) programmatically in typescript for further functional flow. I tried below Office.context.user.emailAddress …
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Office “Add-in Error” or remaining stuck on the loading screen.
An Office Add-in developed with Office.js loads correctly in the local environment, but after deployment it fails to initialize in Word/Excel, showing “Add-in Error” or remaining stuck on the loading screen. Browser developer tools indicate failures in…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Office.js context for multiselected emails in Outlook
Hi, Could you please confirm that method getSelectedItemsAsync from Office.js (1.1) now supports New Outlook and Outlook in browser? I've noticed that emails objects in returned list contains email id that is really from each email itself which wasn't…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Word on the web (SharePoint/WOPI): ContentControl.cannotEdit — ribbon formatting persists after save/reopen; not reproducible on Word desktop
We are seeing this behavior only in Word on the web when editing documents opened from SharePoint (WOPI). We do not see the same issue when opening the same document in Word for Windows / Mac (desktop). We use the Word JavaScript API with rich text…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
NoBootJs Error - Outlook Web App Fails to Load JavaScript on Laptop Only
Problem Description: I am experiencing a critical issue accessing Outlook.com on my laptop that has persisted for multiple days. The same account works perfectly on my mobile phone, confirming this is device-specific. Error Details: Error Code:…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Can i open sharepoint site docx file url using word js api from word desktop/web addin ?
We have requirement to open a uploaded word document present in MS SharePoint site from word addin (desktop and web). Expectation is if document is present in MS SharePoint , open a link to docx file so user can collaborate simultaneously with other…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Popup Login flow not working since microsoft blocked windows opener unexpectedly
We are facing issues with https://login.windows.net/common/OAuth2/authorize?resource=https://manage.office.com since the resource is giving response header as cross-origin-opener-policy : same-origin; report-to="coop-endpoint"due to which…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
How to create a toggle button in the ribbon in the Excel JS API
It definitely seems possible to create a toggle button in VBA (see…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.
Multiselection in Outlook web add-in in Outlook Web/New Outlook with Unified manifest
Hello, We migrated our solution from a COM add-in to an Outlook Web Add-in (Office.js). As part of this transition, we also encouraged our clients to move to the new Outlook. Our add-in uses the Unified Manifest model. We are now trying to implement…
Microsoft 365 and Office | Development | Office JavaScript API
An Office service that supports add-ins to interact with objects in Office client applications.