File Extension Database

Open MSO File

File extension MSO is most commonly associated with an inline E-Mail attachment sent via Microsoft Word 2000, and contains information required to display the attached file within the E-Mail message. Though less common, an MSO file may also refer to a Microsoft Office macro reference file, a MathScript object or a MedleySound Module.

When an HTML E-Mail is composed which contains an inline Microsoft Word 2000 attachment, an additional file called Oledata.MSO is created which contains the information required to render the attachment in its original application. If the recipient opens the E-Mail in Microsoft Outlook, the additional MSO attachment is not seen, the E-Mail message displays correctly and any Microsoft Office attachments can be viewed correctly in the application they were created in. However, if the recipient is using an alternative E-Mail client which is not compatible with Outlook HTML E-Mails they will see the Oledata.MSO file as an additional attachment. Though MSO files can be opened using any text viewer, they are encoded so cannot be understood or edited and contain no information of use to the user. Additionally, modifying the contents of the file or deleting it may render the attached Microsoft Word document unusable so should not be removed.

Microsoft Office macro reference files also use the MSO file extension, and are created when documents created in Microsoft Office are saved as web pages to store links to macros and other embedded objects. These are also encoded and contain no information of use to the user, so should not be opened manually.

MSO files which represent inline E-Mail attachments can only be opened using Microsoft Outlook 2000 or later or any other E-Mail client which is compatible with embedded Office document attachments. MSO files which are produced by MathScript and MedleySound can only be opened successfully in their intended application.

How Can I Open MSO File on Windows

We researched and learned that the best way to open MSO file is to find a MSO file in question in Windows OS File Explorer and double click on it to launch the corresponding application.
If a MSO file is not opened in an application and you instead get a "Windows can't open a file" error message you should try looking for an application which can open the file in question.
If you know the application which can open MSO file then run it and see if there is a File->Open main menu option in the application.
If you don't know the application which function as MSO file opener then try to search online for "MSO viewer", "application to open MSO file" or "open MSO file" queries in the search engine you like.
Install the application you found and check if it can open MSO file

How Can I Open MSO File on Mac OS

We recommend to find a MSO file in question in Mac OS Finder and double click on it to launch the corresponding application.
If a MSO file is not opened in a Mac OS application and you instead get a "There is no application set to open the file" error message you can click on "Search App Store" in the error dialog and Mac OS will show you applications compatible with MSO file.
If you know the Mac OS application which can work as MSO file opener you can choose the "Choose Application..." option in the error box to associate the file extension and open MSO file in it.
If you don't know the application which can open MSO file then try to search for "MSO viewer", "application to open MSO file" or "read MSO file" queries in the online search engine you like.
Install the application you found and check if it can read MSO file

How Can I Open MSO File on Android

If you downloaded a MSO file on Android device you can open it by following steps below:

In the Android apps list on your Android device find "My Files" or "File manager" app and tap to start it.
Tap on "Downloads" folder inside the app.
You should see your downloaded MSO file in that folder.
Tap on the file. If Android device supports opening the file you downloaded it will open in the corresponding app.
If file does not open you can look for the corresponding app that can open the file by searching Android App Store for the "MSO".
If you cannot open the file with the apps from Android App Store it is possible that the file could only be opened on desktop platforms such as Windows or Mac OS. Try searching for "MSO viewer", "MSO file reader" online and see if any desktop applications can open it.
It is also possible that the file you downloaded is outdated and is no longer supported.

How to Open MSO File on iPhone or iPad

To open MSO File on iOS device follow steps below:

We advies to open Files app on your iPhone or iPad device. You can find it by swiping down on the home screen and typing "Files" in the search bar.
Tap on the Downloads folder on the Files app home screen.
You will see all files that you recently downloaded. Tap on the MSO file to view it.
If you have the right app that can open it it will automatically launch and open your file.
If you don't have the app which can open it you need to serch Apple app store for "MSO". This way you can find apps which can open MSO files.
If this doesn't help it is possible that your file could be opened only by the desktop application. To find an app which can open it on desktop look for "MSO viewer" or "MSO file" online in your favorite search engine.