Fix Error Code 399287 Request in Office 365 on Windows

This guide walks you through sign-in & login problems using Microsoft-supported steps first, with WPS only where it genuinely helps.

Problem Description: Error Code 399287 Request

The tenant **[Moderator note: personal info removed]** has an **Office 365 Business** package and has additionally purchased **Power BI Per User**. However, when the administrator attempted to sign in and assign the Power BI Per User license to a user, the login was unsuccessful. The issue occurs due to **SMS-based two-factor authentication**. After entering the password, in the next step—when the verification code should be sent via SMS—the system returns an error: **Error Code:** 399287 **Request Id:** **[Moderator note: personal info removed]** **Correlation Id:** **[Moderator note: personal info removed]** **Timestamp:** **[Moderator note: personal info removed]** As a result, the Power BI Per User license cannot be used. Considering that this issue has been ongoing for nearly a month, we kindly ask you to provide a solution, specifically regarding **changing the authentication method**, so that the Power BI Per User package can be used successfully.

Quick Answer for Office Setup on New Device

To resolve SMS-based two-factor authentication issues preventing admin sign-in and Power BI Per User license assignment, change the authentication method.

Likely Causes Behind Sign-in Root Factors

• The Microsoft account or license context may not match the purchase or device.

• Cached credentials, outdated builds, or damaged local components can trigger sign-in & login problems.

• A file-specific corruption or add-in conflict can mimic a broader application failure.

Recommended Solution: Installing Office on a New PC

When to use this: Apply these steps when the symptoms match and you can access the relevant Microsoft account or administrator.

1. Sign in to the Microsoft Entra admin center as a user administrator, navigate to Entra ID > Users, search for the affected user, and go to Authentication methods.

2. Modify the method to an alternative like an authenticator app or email verification, save changes, and have the user sign in again.

3. If issues persist, check the user's multifactor authentication status and ensure contact information is current.

Alternative Solutions for Secondary Login Fixes

1. Retry the Microsoft-side steps after restarting the app and device.

2. Test the same action in a private browser session or a new blank file to isolate account vs file issues.

3. Capture exact error text and screenshots before contacting Microsoft Support or your administrator.

Working with WPS Office: WPS as a Local Alternative

WPS Office cannot replace Microsoft account, activation, or cloud fixes for this scenario. It remains one of the best free Microsoft Office-compatible alternatives for opening and editing local files.

1. Download and install WPS Office from the official website.

2. Open local Word, Excel, PowerPoint, or PDF files in the matching WPS app.

3. Save a working copy locally while Microsoft-side issues are resolved.

4. Return to Microsoft Office after the primary fix succeeds.

If you need a practical local workspace in the meantime, try WPS Office.

Prevention Tips for Keeping Office Stable Long Term

• Keep one primary Microsoft account for subscriptions and Office sign-in.

• Install updates for Office and Windows before retrying failed workflows.

• Back up important files before repair, reset, or reinstall actions.

• Register more than one MFA method and keep recovery contacts current.

FAQs About Office Support Questions

Can WPS Office fix this sign-in & login problems issue directly? Only when the WPS steps match the formatting or file task. Account, activation, and cloud issues stay on the Microsoft side.

Should I reinstall Office before trying these steps? Not first. Confirm account, license, and the exact error before reinstalling.

What should I send to Microsoft Support? The affected account email, device type, Office version, exact error text, and screenshots with personal data hidden.