By default, HTML outputs have an .html extension, but you can change the extension to .htm by adding some metadata to the DITA Map file used to generate the output.
Procedure
Start Publication Manager and open the publication.
The Browse Repository window is displayed.
Right-click the bookmap and select Check out with in Oxygen XML Author.
Put your cursor at the start of the ending Bookmeta tag, press Enter, and select othermeta from the list that displays.
In the Attributes dialog box, enter .htm in the content field and enter htmlExtensionin the name field.
The topic Sample DITA Map set to produce .htm output files provides an example of how the attributes should be set to produce an output with an .htm extension.
Check in the bookmap, save the publication, and produce the HTML output.
