.MSO File Type
File extension: MSO or .mso
Author of the .mso file extension: Microsoft Corporation
Category: Miscellaneous files
Programs that use the .mso file type: Microsoft Word and Outlook create and use the file.
Explanation of .mso file extensions:
Microsoft Word 2000 is a word processing program that lets you create and share documents using a variety of writing tools. You can send HTML messages with an attached Microsoft Office document which is then sent as an Outlook HTML message rather than an Office Envelope message.
This oledata.mso file contains information required for rendering the attached document its originating program which is called "round tripping." The .mso file contains no useful information for the user. This file is not editable. While there is not useful information to the user, deleting the file could render the attached file unusable.
If you do not have Outlook 2000 installed and receive an email created with MS Office 2000, the oledata.mso file appears as an additional attachment.
Typical problems associated with the .mso file extension:
Problems with .mso files occur between users of different versions of Office. For example, an Outlook 98 user who receives an email created with Word 2000 and sent via Outlook 2000 containing the oledata.mso file may have trouble viewing emails and bitmaps.
Another common .mso problem occurs when users try to open the .mso file manually.
Solutions/Recommendations:
If you are an Office 2000 users corresponding with users of earlier versions of Office, consider using the Paste Special command rather than the standard Paste command. For Office 98 users, choose Paste Special/Device Independent Bitmap. For all other users, choose Paste Special/RTF format. Alternatively, use Outlook to compose your messages rather than Word 2000.
If you are tempted to open a .mso file manually, don’t. There’s no useful information in there for you.
Associated links:
Microsoft Knowledgebase article about .mso - http://support.microsoft.com/kb/222330
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