You can easily save an email as an HTML file in Outlook with below steps:

1. Shift to the Mail view, open the mail folder containing the specified email you will save as HTML file, and then click to highlight the email in the mail list. See screenshot:

2. Click File > Save As.

3. In the opening Save As dialog box, please: (1) Specify the destination folder where you will save the new HTML file in; (2) The new HTML file will be named with email subject automatically. Rename it in the File name box as you need; (3) Select HTML from the Save as type drop down list. See screenshot:

4. Click the Save button.

And now the selected email has been saved/exported as an HTML file already.

If you have Kutools for Outlook installed, you can apply it Save as File feature to batch save multiple selected emails as individual HTML files in Outlook easily. Please do as follows:

1. Select multiple emails you will save as HTML files, and click Kutools > Bulk Save S. See screenshot:

2. In the Save messages as other files dialog box, please (1) click the Browse button  to specify the destination folder you will save the HTML files, (2) only check the HTML format option in the Select Save file format section, and then (3) click the OK button.

Now you will see each selected email is exported as individual HTML file and saved in the specified destination folder. See screenshot:

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