A family of Microsoft word processing software products for creating web, email, and print documents.
The error indicates a problem when Word tries to share the document via a mail client or online service.
If sharing from Word via email and a “MAPI failure” or similar error appears, the most common cause is that the default mail client is the New Outlook app, which is not MAPI‑compliant and cannot be used for sending files directly from Office apps.
To resolve this:
- Open Outlook on the PC.
- Use the toggle in the upper‑right corner to switch from New Outlook to Classic Outlook.
- After Classic Outlook opens, close Word and reopen it.
- Try sharing the document again from Word.
If Word itself is failing with general errors when trying to share or send, run an Online Repair of Office:
- Close all Office apps.
- Open Windows Settings → Apps → Installed apps (or Apps & features).
- Find the Office product, select Modify → choose Online Repair, and complete the repair.
- Restart the computer and test sharing again.
If the error appears only when sharing to OneDrive/SharePoint from within Word, try sharing the document from OneDrive/SharePoint directly instead of from Word, following the standard document sharing steps:
- Save the document to OneDrive or SharePoint.
- In OneDrive/SharePoint, select the file, choose Share, adjust Link settings and permissions, then send or copy the link.
References:
- I am unable to share my file either as a presentation or document type or pdf type by none of the microsoft office apps (Word, Excel, Powerpoint). It is continuously showing "Mapi Failure" and "Unable to Share" errors. What can I do? - Microsoft Q&A
- Share your documents
- how to fix word error - Microsoft Q&A
- We're Sorry but Word Has Run Into an Error - Microsoft Q&A