How to Convert Thunderbird MSF File to PST - Real Mailbox Files

If you want to transfer your data from Thunderbird to Outlook firstly, you need to know about the file formats supported by the respective email platforms.
Data file format is the primary concern while initiating any kind of migration from one mail client to another. If you are using an email client that understands MBOX/MSF file format and want to switch to MS Outlook, then your MSF file / MBOX file needs to be converted to PST format. However, before proceeding with the conversion, first we need to know what are MSF and PST.

PST (Personal Storage Table)

PST is a Personal Storage Table file that belongs to MS Outlook. The data file stores user’s account data including all mail folders and other personal items, such as appointments, contacts, email attachments, and more. These files are located on the local machine within a default store folder.

MSF (Mail Summary File)

The MSF file type is primarily associated with Thunderbird. Thunderbird is an email client by Mozilla, which stores the contents of each email folder as two types of files:
With No Extension: It is the mail storage file in MBOX format. Though the file is created with no extension but it is the MBOX file which consists of the collection of messages representing a mail folder in Thunderbird client.
With .msf Extension: It is the index (Mail Summary File) assigned to each email folder in the Thunderbird profile that contains message summary of the emails stored within the corresponding MBOX file.
If we want to import/export mails to any other program, we need to import/export them from the file with no extension, i.e. the MBOX file. Thus, the messages from Thunderbird is possible but not as MSF to PST but rather as MBOX to PST conversion.

Switching Thunderbird .msf to Outlook .pst

MS Outlook is the most widely used e-mail client, which stores emails along with user’s personal data in a PST format. Although, Thunderbird is a free and open-source application, yet it lacks functionalities that are in Outlook, i.e. absence of personal storage management. Therefore, it cannot be regarded as a complete desktop emailing program.

Is it Possible to Open MSF File in Outlook?

No, MSF files are the proprietary summary files that belong to Thunderbird and are not suitable for conversion of messages from the client owing to the fact that it is not an email repository. Therefore, conversion of mailbox to PST needs to be performed instead.
Manual Method: It can be achieved without using any software. Add-ons are provided by external providers that may be helpful for an indirect conversion of individual count of messages from Thunderbird to Outlook and not collective.
Using a Commercial Tool: A third party tool can be used to convert bulk of email contents from Thunderbird mailboxes to PST without any end user efforts being required.

Important Note:MSF files are only index files. They do not contain any sort of data. Hence, converting them has no value at all. People with less technical knowledge often mistake MSF files with the real mailbox files of Thunderbird (i.e., the files with no extension).
Hence, both in manual and professional solution, please replace MSF files with MBOX files for accessing the real data in Outlook.

Manual Method to Export Thunderbird data into Outlook PST

Following are some steps, which need to be followed if you want to export Thunderbird data into Outlook manually.
NOTE: An add-on namely import/export tools is required for the conversion.

• Run Thunderbird email client
• Open the folder that you want to export messages from
• Select emails
• Right-click on selected emails and click on the “Save As” option and choose the desired file type. For instance - EML

NOTE: Being simple text based message storage, Outlook can read EML type files, though not officially but it does.

• Save the selected messages in destination folder and click on select folder.
• Run MS Outlook
• Create a new folder for storing the converted messages
• Enter a desired name and click on OK.
• Select all emails exported from Thunderbird
• Drag all emails to the newly created folder on MS Outlook.
• After a successful import process, all emails can be viewed.

This method will be useful if there you have a limited number of emails and don’t require the message formatting to be retained along with the original head information.

Drawbacks of Manual Method

• Risk of data/message formatting loss & internet header modification
• Time-consuming (you have to drag and drop each email)
• Requires end users to put in manual efforts for the entire task
• Emails will lose their SMTP header

NOTE: Thunderbird should be installed and configured on your system.
To overcome these issues you can use any commercial tool that can effectively deliver efficient data transfer services.

By Using a Professional Tool

As an alternative for Thunderbird MSF to PST, you can get a one-click solution. MBOX Converter is recommended for converting message storage from Thunderbird to Outlook PST file. This tool will help you convert multiple MBOX files to PST and other featured formats.
One can easily install and purchase this software from its official website.
Additionally, this tool ensures

• Data accuracy
• High speed conversion
• No loss of data / metadata during or after conversion
• Facility of previewing the messages
• Bulk size data transfer

Steps to Convert Thunderbird MSF to PST:

• Start the DataHelp software and click the Select Files button.

• Use the Select Folder option to import multiple MBOX files (Not MSF, since it has no data).

• Now, click the Convert button once the files are added to the software.

• Click Browse(..) to select the location to save the PST files and select Ok button.

• Once the files are converted, click Ok on the confirmation window.

Conclusion
Using MBOX Converter, you can easily convert your Thunderbird .msf to Outlook .pst. It not only saves your time but also assures you of full data conversion along with security of the contents.

Other than that if you are seeking to convert msf to unicode pst, then the above-suggested information regarding MSF & the third party tool proves to be helpful in those scenarios also.