Outlook Error 0x80040112 Outlook Invalid Class String

Code: 0x80040112 Category: Outlook Rating: 4.5/5 (66 reviews) Updated: 2026-04-04
Outlook Error 0x80040112 Fix troubleshooting screenshot

Outlook Error 0x80040112 Fix is one of the most searched Outlook problems in enterprise and home environments. Outlook Error 0x80040112 Fix: IT teams document Outlook Error 0x80040112 Outlook Invalid Class String because the code appears in Event Viewer, Office telemetry, or on-screen dialogs without clear next steps. WinAssistPro maps 0x80040112 to verified repair steps used in production support.

What is 0x80040112?

0x80040112 is a Outlook-specific failure code associated with Outlook Invalid Class String. When this error appears, Outlook cannot complete the requested operation until the underlying configuration, permission, or connectivity issue is resolved.

Verify Autodiscover with Microsoft Remote Connectivity Analyzer if 0x80040112 appears during first-time account setup.

Run Outlook in Safe Mode (outlook.exe /safe) to isolate COM add-ins that trigger 0x80040112 during startup.

Outlook error 0x80040112 often reappears after incomplete updates. Capture the exact build number, channel, and user context before changing profiles or reinstalling components.

When outlook invalid class string persists, compare a healthy device on the same network segment. If 0x80040112 is isolated to one account, rebuild local cache before tenant-wide changes.

What are the symptoms of 0x80040112?

  • Outlook stops responding or closes unexpectedly when outlook invalid class string occurs.
  • Event Viewer or application logs show 0x80040112 within the same minute as the user-visible failure.
  • Repeated prompts, failed operations, or missing features appear until Outlook is restarted or the profile is reset.
  • Safe Mode or web-only access works while the desktop client still throws 0x80040112.

What causes 0x80040112 in Outlook?

  • Corrupted Outlook profile, add-in, or local cache prevents the operation tied to 0x80040112.
  • Third-party security software filters traffic or files that Outlook needs, surfacing 0x80040112.
  • Network latency, proxy misconfiguration, or TLS inspection breaks Outlook communication when 0x80040112 is logged.

How to fix 0x80040112 step by step

  1. Verify the error code

    Confirm 0x80040112 in Outlook logs, Event Viewer, or the dialog. Screenshot the full message for change-control records.

  2. Restart and patch

    Close Outlook, reboot Windows, install pending OS and Office updates, then retest the exact workflow that triggered 0x80040112.

  3. Repair Microsoft 365

    Settings > Apps > Installed apps > Microsoft 365 > Modify > Online Repair. This restores Outlook binaries linked to 0x80040112.

  4. Apply category fix

    Create a new Outlook profile in Control Panel > Mail and migrate only the affected mailbox to test PST/OST integrity.

  5. Validate with test account

    Sign in with a clean profile or temporary user. If 0x80040112 disappears, migrate data instead of reinstalling the whole device.

Quick reference table

Field Value
Error code0x80040112
ProductOutlook
SeverityMedium to High
Typical fix time10–30 minutes
Requires admin rightsSometimes

Frequently asked questions about 0x80040112

What does Outlook error 0x80040112 mean?

Error 0x80040112 signals outlook invalid class string. It indicates Outlook could not finish the operation because of configuration, permission, or connectivity limits.

Can I ignore 0x80040112?

No. Unresolved 0x80040112 events in Outlook can lead to data loss, sync backlog, or recurring crashes for the same users.

How long does a 0x80040112 fix take?

Most Outlook cases clear in 10–30 minutes after restart, update, and Online Repair. Profile rebuilds may add another 15–45 minutes.

Does Microsoft support document 0x80040112?

Microsoft documents many HRESULT and stop codes. WinAssistPro consolidates 0x80040112 fixes into a single ordered checklist for faster desk-side recovery.

User reviews

“The 0x80040112 walkthrough fixed our Outlook issue in one pass. Clear steps and no fluff.”

Daniel R. — 2026-03-12 — 5/5

“We hit 0x80040112 during rollout. This guide mapped symptoms to the right repair path quickly.”

Priya M. — 2026-02-08 — 4/5

“FAQ section answered the exact Outlook questions our help desk was getting.”

Marcus T. — 2026-01-19 — 5/5