You Have an MSG File and Outlook Won’t Open It
You just received an important email as a standalone MSG file, perhaps from a colleague or downloaded from a backup. You double-click it, expecting it to open in Microsoft Outlook, but nothing happens. Or worse, Windows asks you to “Choose an app” from a list of programs you don’t recognize.
This is a common roadblock for professionals who work with archived emails. The MSG file format is Outlook’s native format for saving individual emails, contacts, or appointments outside your mailbox. But when the file association is broken or you’re using a different email client, opening it becomes a puzzle.
This guide will walk you through every method to open MSG files in Outlook, from the simple double-click to advanced troubleshooting when things go wrong. By the end, you’ll be able to access any MSG file’s contents, whether you need to view a single email or import a whole batch into your mailbox.
What Exactly Is an MSG File?
Before we fix the problem, it helps to understand what you’re working with. An MSG file is a container created by Microsoft Outlook. When you drag an email from your inbox and drop it onto your desktop, Outlook saves it as an MSG file.
This file contains all the elements of the original email: the sender, recipients, subject, body, attachments, and even metadata like timestamps and conversation threads. It’s a complete snapshot. The key point is that MSG is a proprietary format designed primarily for Outlook. While other email programs might handle it with add-ons, Outlook is its native home.
Why Your MSG File Might Not Open Automatically
Several issues can prevent that smooth double-click experience. The most common culprit is a broken file association in Windows. This means your operating system has forgotten that MSG files should be opened with Outlook. This can happen after installing new software that claims the .msg extension, after major Windows updates, or if Outlook was reinstalled.
Another frequent scenario is trying to open the file on a computer where Microsoft Outlook is not installed at all. You might be using Outlook on the web, Windows Mail, Thunderbird, or a Mac. Without the full desktop Outlook application, the system has no default program to handle the file.
Finally, the MSG file itself could be corrupted. This is less common but possible if the file was interrupted during download, stored on a failing drive, or created by a non-Outlook tool that didn’t follow the format specifications correctly.
The Standard Method: Open MSG Files Directly in Outlook
If you have Microsoft Outlook installed and it’s generally working, this is the first and easiest method to try.
Simply navigate to the MSG file in Windows File Explorer. Double-click the file. If Outlook is correctly set as the default program, it will launch (if it’s not already open) and display the email in a new window. You can read it, reply, forward, or save it to your mailbox.
To save it into your Outlook folders, you drag and drop. Open your Outlook folder pane so you can see your mailbox structure (like Inbox, Sent Items, or a custom folder). Then, click and hold the MSG file from your desktop or download folder, drag it over the desired folder in Outlook’s navigation pane, and release. The email will now reside in that folder as if it had always been there.
Using the Open Command Within Outlook
What if double-clicking doesn’t work? You can force Outlook to open the file from inside the application itself.
First, open Microsoft Outlook. Go to the File menu in the top-left corner. Select “Open & Export” and then choose “Open Outlook Data File.” A file browser window will appear. Crucial point: by default, this dialog is set to look for PST files (Outlook Data Files). You need to change the file type filter.
In the bottom-right of the file browser window, click the dropdown menu that says “Outlook Data File (*.pst)”. Change it to “Outlook Data Files (*.pst; *.ost; *.msg)”. Now, navigate to your MSG file, select it, and click “Open.” The email will open in a separate window.
This method bypasses Windows file associations entirely, making it a reliable fallback when the direct double-click fails.
What If You Don’t Have Outlook Installed?
Not everyone has a licensed copy of Microsoft Outlook on their machine. You might be on a shared computer, using a different primary email client, or on a Mac. Here are your practical options.
Use Outlook on the Web (Free)
If you have a Microsoft account (like an Outlook.com, Hotmail, or even an Office 365 work/school account), you can use the free web version. While you can’t directly upload an MSG file to Outlook on the web, you can use a workaround with OneDrive.
Upload the MSG file to your OneDrive. Once uploaded, right-click the file in OneDrive and select “Open in App.” If the “Open in App” option isn’t available or doesn’t work, change the file’s extension. Rename the file from “email.msg” to “email.eml”. OneDrive and most web browsers are better at recognizing the EML format. After renaming, try opening it again; it may open in your browser or offer to download, which you can then open with other programs.
Convert the MSG File to a Universal Format
The most versatile solution is to convert the MSG file to a format that any device can read. The EML format is a standard for email messages and is widely supported.
You can use free online conversion tools. Search for “MSG to EML converter” and you’ll find several reputable websites. Upload your MSG file, download the converted EML file, and then you can open it in virtually any email program like Windows Mail, Thunderbird, Apple Mail, or even a text editor to see the raw headers and body.
Important: Be cautious with sensitive emails. Only use online converters from trusted sources and understand that you are uploading your email content to a third-party server. For confidential messages, it’s safer to use a dedicated, installable conversion software on your own computer.
Use Alternative Free Email Clients
Some free desktop email applications can natively open MSG files or have extensions that enable the functionality. Mozilla Thunderbird, a popular open-source client, can handle MSG files with the help of an add-on called “ImportExportTools NG.” After installing this add-on, you gain the ability to import and open MSG files directly.
Windows 10 and 11’s built-in “Mail” app, however, does not support MSG files. It’s designed for live email accounts, not standalone message files.
Troubleshooting Common MSG Opening Errors
Even with Outlook installed, you might encounter specific error messages. Let’s break down the fixes.
“Windows Cannot Open This File” or “Choose an App”
This is a file association issue. You need to tell Windows to always use Outlook for MSG files.
Right-click the MSG file and select “Open with” > “Choose another app.” In the list that appears, look for “Microsoft Outlook.” If you see it, select it and, most importantly, check the box that says “Always use this app to open .msg files.” Then click OK.
If Outlook is not in the list, click “More apps” and scroll down. You might need to click “Look for another app on this PC.” You will have to navigate to the Outlook executable file. The typical path is: C:\Program Files\Microsoft Office\root\OfficeXX\OUTLOOK.EXE (where XX is your version number, like 16). Selecting this executable will set the association.
Outlook Opens But the File Appears Blank or Corrupt
If Outlook opens but the message window is empty or shows garbled text, the file is likely corrupted. First, try obtaining a fresh copy of the MSG file from the original source.
If that’s not possible, you can attempt recovery. There are specialized email recovery tools available that can sometimes extract readable text and attachments from damaged MSG files. These are third-party commercial software options. As a last resort, you can try opening the MSG file with a text editor like Notepad++. You won’t see the formatted email, but you might be able to sift through the raw data to find the plain text body and important headers like the subject and sender, which are often still recoverable.
Outlook Says “Cannot Open File” or “Access Denied”
Check the file’s location and permissions. Is the MSG file stored on a network drive, USB drive, or a folder with restricted permissions? Copy the file to your local desktop or Documents folder and try opening it from there. Also, ensure no other program is currently using the file. Sometimes, antivirus software can temporarily lock files during a scan.
Also, verify the file integrity. Right-click the file, select Properties, and check the file size. An MSG file should typically be at least a few kilobytes. If it shows 0 KB or an unusually small size, the file is incomplete.
Advanced: Batch Importing Multiple MSG Files
If you have a folder containing dozens or hundreds of MSG files from an archive, opening them one by one is impractical. You’ll want to import them all at once into an Outlook folder.
Outlook doesn’t have a built-in “Import Folder of MSG Files” button, but you can achieve this with a simple drag-and-drop. Open the folder containing the MSG files in Windows File Explorer. In Outlook, navigate to the folder where you want the emails to go. Select all the MSG files in File Explorer (Ctrl+A), then click, drag, and drop them all onto the Outlook folder. Outlook will import each one as a separate email item.
For very large batches, this method can be slow. For a more robust solution, you can use Outlook’s official “Import and Export Wizard” to import from another program or file, but it requires the files to be in a PST archive first. You would need to use a separate tool to combine the MSG files into a single PST file, then use the wizard to import that PST.
Your Action Plan for MSG Files
Start with the simple double-click. If it works, you’re done. If it doesn’t, open Outlook and use the File > Open & Export method to bypass the Windows association. For computers without Outlook, convert the file to EML using a trusted online tool or desktop software, which becomes a universal key for opening the email anywhere.
Remember to reset the file association in Windows if you plan to work with MSG files regularly. This saves time and frustration in the future. For archived communications, consider dragging important MSG files directly into your Outlook mailbox to keep everything in one searchable, backed-up location.
MSG files are meant to preserve important communications. With these methods, you’re no longer locked out of that information, whether you’re on a work PC with full Office or a personal device using free tools.
