Can't download .fbx

[janlucvd]

I’m ordering 3D models created, but when my client sends me an .fbx, it downloads as a .txt. file! Because of this she had to put the model on a 3rd party site for me to download from there. Is this a new bug or am I doing something wrong? She says this is a problem that others experience, but I’ve never had this happen until last week.

Please advise. Thanks!