Is it better to use a tooltip or take the user to a separate page to communicate to them what is doable or not?

Question

I'm working on an app that will be integrated into a video conferencing client.

In a nutshell, what this app does is allow participants in the call to share files. The app will have two sections for each participant:

1. A private file section - participants can upload any file here, but it won't be visible to anyone else in the call

2. A public section - any file that a participant introduces will be publicly visible, ie, visible to everyone in the call

Because this is a legal proceeding and our userbase is comprised of an older demographic, it is imperative that they need to be able to preview the files that are about to introduce; inadvertently introducing the incorrect file that everyone in the call will now have access to can have legal consequences.

Unfortunately, due to certain technical limitations, only certain file types (JPEG, GIF, PDF) can be previewed. Some files such as XLS, DOC, MP4, MOV, etc. cannot be previewed, at least for the time being.

So once a file is in the Public section, anyone in the call will have the ability to Present, Preview, and Download it.

So here's my problem - since presenting and previewing is not available for certain file types, the only way for participants to see it is if they downloaded it. What would be clearest way to go about that, especially considering the demographic in our userbase?

Option 1:

• Disable the Present and Preview buttons for unsupported file types
• On hover, display a tooltip communicating to the user that previewing is not available for this file type

Pros:

• User doesn't have to click on these buttons only to get into an error (preview not available) state, ie, less clicks to realize what is doable or not

Cons:

• Since we have an older userbase, the tooltip might be too small for them. And they might not easily figure out how to download a file. Yes, there's a Download button on there, but they might not be able to easily make a connection that this is what they need to do as an alternative, even though the tooltip says it

Option 2:

• Keep the Present and Preview buttons enabled. If the user clicks on these buttons, take them to an error (preview not available) page

Pros:

• Very clear to the user as to what the alternative path is for them with a very obvious "Download" button

Cons:

• User has to click on these buttons only to realize such functionality is not available, ie, 2 clicks only to get into an error state

Answer 1

I would avoid the tooltip, for the cons described.

Regarding the option of the warning page, I suppose that somewhere in the application there will be an explanation of what type of files are not previewable, so I would not insist on negative messages such as "preview not available", which in addition to repetitive is somewhat frustrating.

You can use the icons of these files as a reminder preview of what type of file it is, and a message that they are only visible after downloading:

Answer 2

I think you simply show a Preview button next to every filename. If the file is a supported type, the file opens in the preview window. If it's unsupported, it launches in the user's native desktop app.

This is how files work in web browsers. I can open a PDF in the browser window, but if I click on a .doc, it launches Word.

Answer 3

No need to worry about changing your flows. Those files can be previewed.

For your issue with MOV and MP4, they can be supported. You can convert them on the DB or on the client's device to webm or mp4 (not verified the linked package, but the method fits what I was thinking: using ffmpeg). I'd like to mention that mp4 should be widely supported, unless your audience is using an older variant of Firefox.

The Microsoft files (XLS or Docs) can be uploaded to OneDrive then that page can be previewed, or you can use Google Doc's or Microsoft's previewers (see this answer)