Exporting Thunderbird emails to Outlook PST manually involves several steps, as Thunderbird and Outlook use different email formats. Here's a step-by-step guide to help you accomplish this task:

Step 1: Install Thunderbird and Outlook

Ensure you have both Mozilla Thunderbird and Microsoft Outlook installed on your computer before proceeding.

Step 2: Set up an IMAP Email Account (Optional)

If you don't already have an IMAP email account, you can set up a free email account (e.g., Gmail) in Thunderbird as IMAP. This will allow you to synchronize your Thunderbird emails with the email server and later access them in Outlook.

Step 3: Configure Thunderbird for IMAP Account (Optional)

Open Thunderbird and go to "Tools" > "Account Settings."

Click on "Server Settings" under your IMAP account.

Ensure that the "Check for new messages at startup" and "Check for new messages every XX minutes" options are enabled.

Click on "Synchronization & Storage" and select "Keep messages for this account on this computer" to store messages locally.

Close the Account Settings window.

Step 4: Export Thunderbird Emails to EML Files

Open Thunderbird.

Select the folder you want to export (e.g., Inbox) from the left-hand side folder list.

Press "Ctrl + A" to select all emails in the folder or use "Ctrl + Click" to select specific emails.

Right-click on the selected emails and choose "Save As" from the context menu.

Choose a location to save the emails, create a new folder if necessary, and click "Select Folder."

Thunderbird will save the emails as individual .eml files in the specified location.

Step 5: Convert EML Files to Outlook PST

To import emails from Thunderbird into Outlook, you need to convert the EML files to PST format. You can use a third-party tool or use Microsoft's free tool called "PST Capture Tool" for this conversion. Here's how to use the PST Capture Tool:

Download and install the Microsoft PST Capture Tool from the official Microsoft website.

Open the PST Capture Tool and click "Add Forest" to specify your Active Directory Forest.

Click "Add Mailbox Import List" to create a list of mailboxes for importing.

Click "Add PST File" to add the EML files exported from Thunderbird.

Click "Start" to begin the import process.

Once the conversion is complete, you'll have PST files containing your Thunderbird emails.

Step 6: Import PST File into Outlook

Open Microsoft Outlook.

Go to "File" > "Open & Export" > "Import/Export."

Select "Import from another program or file" and click "Next."

Choose "Outlook Data File (.pst)" and click "Next."

Click "Browse" to locate the converted PST file and click "Next."

Select the folder you want to import (usually "Inbox" or "All folders") and choose the option that suits your preference (e.g., "Import items into the same folder").

Click "Finish" to start the import process.

Outlook will now import the Thunderbird emails from the PST file into your Outlook account. Once the import is complete, you should see your Thunderbird emails in Outlook.

Greetings,
Peter