Help please! My customer got a HTML file not zip

[GraceHavenArt]

I made my first sale to a friend (thankfully). The reason I say thankfully is because she purchased a digital download but says she got a html file, not the zip file or pdf in the listing. Is the HTML standard and the link to the zip file or have I done something wrong? I've emailed her the files separately but obviously want to fix it for future sales.

HELP PLEASE!

[CanningCrafts]

If you have a zip & pdf for the uploads in your product listing, that is what should download. Did your friend click the "Download Files" button on the Purchases page? If an html was downloaded, I'm wondering if your friend just accidentally downloaded from the browsers "Save Page as" menu. 

[Chaiv]

Your customer's computer doesn't recognize the zipped file so it's relabeling it as an html. They're probably running an older version of Windows. You can't fix the issue for her. The only thing you can do is send her the file(s) unzipped, which you've already done.