An unknown error has occurred in Outlook

Symptoms


In Microsoft Outlook, you may receive one of the following error messages when you try to read, send, receive, or delete an email message.

Error message 1:

An unknown error has occurred. 0x80040119
Error message 2:
An unknown error has occurred. 0x80040600

Or, when you try to delete email messages, you may receive the following error message:

Messaging interface has caused an unknown error

Resolution


The error may be caused by a corrupted Outlook Data File (*.pst) in the Outlook profile.

To repair the corrupted file, follow these steps.

Step 1: Locate the default *.pst file that is using the Outlook profile

  1. In Control Panel, open the Mail the item.
  2. Click Show Profiles. Select the Outlook profile that experiences the issue, and then click Properties.
  3. Click Data files.
  4. Make a note of the location of the default *.pst file. The name of the default *.pst file contains a black circle with a check mark.
    *.pst file

Step 2: Run the Outlook Inbox Repair Tool (SCANPST.exe) to repair the *.pst file

  1. Exit Outlook.
  2. Open the Outlook Inbox Repair Tool (SCANPST.exe).
  3. In the Enter the name of the file you want to scan box, type the location of the *.pst file.
  4. Click Start.

Where to find the Outlook Inbox Repair Tool

Outlook 2013

32-bit version of Windows: C:\Program Files\Microsoft Office\Office15\
64-bit version of Windows: C:\Program Files (x86)\Microsoft Office\Office15\
64-bit Outlook: C:\Program Files\Microsoft Office\Office15\

Office 365 Home or Business, Outlook 2013 Click to Run

Any version of Windows: C:\Program Files\Microsoft Office 15\root\office15\

Outlook 2010

32-bit version of Windows: C:\Program Files\Microsoft Office\Office14\
64-bit version of Windows: C:\Program Files (x86)\Microsoft Office\Office14\
64-bit Outlook: C:\Program Files\Microsoft Office\Office14\

Outlook 2007 

32-bit version of Windows: C:\Program Files\Microsoft Office\Office12\
64-bit version of Windows: C:\Program Files (x86)\Microsoft Office\Office12\

Original help link: https://support.microsoft.com/en-us/help/814441/an-unknown-error-has-occurred-error-message-in-outlook