When I'm installing Whatsapp on my Nokia Lumia 520, running on Windows Phone 8.1, I get the 80073cf9 error. It's only since yesterday. Does anyone know how to fix this?
Might be this link will help you in rectifying the issue.
The solution described in the above link is,
- Check your regional settings. Undo any changes you made recently.
- Turn on your Location.
- Check your storage sense. Make sure that the apps are installed to phone.
- Soft reset your phone.
- Hard reset your phone.
The details on How to perform a soft and hard reset can be found in this discussion.
Hope it helps!