To learn which formats can be uploaded, please click here.
If your file is rather large, the best work around is for you to store your file somewhere online that makes it accessible via a URL, and then use the 'Import from URL' button on https://promethease.com. Here are some of the methods that our users have told us are the most successful:
iCloud using the hack described here https://alphathiel.de/magentacloud-hack-direkt-auf-freigegebene-dateien-zugreifen/ Basically, open the indirect download link in chrome, right click, go to inspect, click on console, then click the download button on the page, and then copy the URL that pops up on the console.
Dropbox seems to work well, but their free product is limited to 2G.
Google drive is an option, but the URLs it generates require a google account to access, which the promethease.com software does not have. Instead There's a hack (https://stackoverflow.com/a/47581609) around that by generating a Google Drive API key and embedding that in the URL, which produces a URL that does work without logging in (test it from an incognito/private window). The a direct URL with no login needed will resemble : https://www.googleapis.com/drive/v3/files/abc123def456/?key=ABC0987POIUQWERTYUIQWERTY&alt=media
Magentacloud seems to work well
Be sure to use a PC or laptop when attempting this workaround.