I am facing the same issue with file download. It happens with zip, pdf, and docx.
I have tried:
ChatGPT Windows App
Chrome
Brave
Edge
I hope that OpenAI fixes it soon. I have wasted a few hours trying to fix it.
Trying various browsers (including incognito/private), clearing caches, and uninstalling and reinstalling the ChatGPT Windows Desktop App.
The only thing that works at this time is to download the file from my iPhone app. Needless to say that it is really cumbersome to download on iPhone and then transfer to my desktop. But it is a workaround that has at least provided me some progress. Sharing here so others can benefit.
I have the same issue and found the mobile download working. This is very frustrating. The last week chatGPT has been very buggy, like sudden whitescreen on windows app, having to reload just to have it crash again, web interface crashing a lot. I dont get whats going on. I hope its just a temporary fluke, if this keeps up I will most likely move away to another.