how to fix "an internal server error occurred, the operation failed, object reference not set to an instance of an object

Question

Thanks in advance,

I have 365 Microsoft subscription, a week back I was able to send purview encrypted emails but now I cannot. Now when try to send a purview encrypted email this notification shows "an internal server error occurred, the operation failed, object reference not set to an instance of an object". I tried on outlook classic, a window "the attempt operation failed. An object could not be found" I tried the reset outlook, deleted outlook account, repair os file, no success. Please advise.

Very respectfully,

Juan C.

Answer 1

Hi J C,

Because New Outlook relies heavily on embedded web components (WebView2), errors like “object reference…” can sometimes appear when its local web cache or cookies are corrupted. Clearing Credential Manager is still useful for sign‑in issues, but it doesn’t reset those web components.

Please try this (New Outlook – cache focus):

Confirm on the web: Test encryption at Outlook.com (New message > Options > Encrypt).

If it fails on the web as well, that would point to an account or service-side issue rather than the local app.

Clear Edge / WebView cache (local):

• Close New Outlook
• Windows Settings > Apps > Installed apps > Microsoft Edge WebView2 Runtime > Advanced options > Repair (if available)
• Then go to Settings > Apps > Installed apps > Outlook (new) > Advanced options > Reset
• Reopen New Outlook, sign in, and test Encrypt again

Also clear cookies/site data (Edge): Edge Settings > Cookies and site permissions > Manage and delete cookies and site data > See all site data and permissions

Remove site data for outlook.office.com, outlook.com, and office.com, then test again.

Quick question: Does encryption work in Outlook.com (web)? (Yes / No)

Please let me know if this proves useful to you, or if you would like further assistance.

I'm looking forward to your reply.

---

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Answer 2

Follow these steps to troubleshoot Microsoft Purview Message Encryption failing with internal server/object reference errors when sending from Outlook:

1. Remove cached Office/Outlook credentials
   1. Close Outlook and all Office apps.
   2. Open Control Panel → User Accounts → Credential Manager.
   3. Under Windows Credentials and Generic Credentials, find any entries related to Office, Outlook, Microsoft 365, or the affected account.
   4. Expand each related credential and select Remove.
2. Remove old Office/Outlook sign-in state on the device
   1. Close all Office apps.
   2. Press Windows + R, type appdata, and press Enter.
   3. Go to Local → Microsoft.
   4. If present, delete cached identity folders such as OneAuth and other sign-in state folders as advised by support (these are recreated automatically when Office is reopened).
3. Remove any unlicensed or wrong account from Windows (if applicable) If the device is not Microsoft Entra joined and an unlicensed or incorrect account is present:
   1. Select Start → Settings → Accounts → Access work or school.
   2. Select the unlicensed/incorrect account and choose Disconnect.
4. Sign back in with the correct, licensed account
   1. Open any Office app (for example, Word or Outlook Classic).
   2. When prompted, sign in using the Microsoft 365 account that has a valid license for Microsoft Purview Message Encryption.
   3. Confirm in File → Office Account that this account is shown as the signed-in account and is activated.
5. Verify connectivity to the Azure Rights Management service On the affected machine:
   1. Open Windows PowerShell.
   2. Run:

            $request = [System.Net.HttpWebRequest]::Create("https://admin.na.aadrm.com/admin/admin.svc")
            $request.GetResponse()
            $request.ServicePoint.Certificate.Issuer
      

   3. Confirm the output shows a Microsoft CA, for example: CN=Microsoft Secure Server CA 2011, O=Microsoft Corporation, L=Redmond, S=Washington, C=US.
   4. If a non-Microsoft CA appears, reconfigure the firewall or TLS inspection so the client can establish a direct, unbroken TLS connection to the Azure Rights Management service. See the Firewalls and network infrastructure guidance in the referenced article.
6. Check sensitivity labels and permissions If sensitivity labels are used on the emails:
   1. Ensure the label configuration in Microsoft Purview assigns permissions that allow recipients (and the sender) to access and send encrypted messages.
   2. Adjust label permissions if necessary so they are not overly restrictive.
7. Test again in Outlook Classic and New Outlook
   1. Start Outlook Classic with a clean profile if possible.
   2. Compose a new email, apply the Purview encryption/sensitivity label, and send.
   3. Repeat in New Outlook for Windows.

If the issue persists after completing these steps (credentials cleared, correct licensed account in use, RMS connectivity verified, and labels checked), contact Microsoft Support for deeper investigation, as recommended in the documentation.

---

References:

• Resolve Microsoft Purview Message Encryption issues