Preview Pane instability with Dropbox's online-only files

I have the Dropbox desktop app installed on my Windows 10 system, and I have selective-sync turned on. The way it works is that any files I haven't accessed in some amount of time (say, 60 days), get removed from my local storage, and stored online-only. They still appear in my folder hierarchy and are downloaded as-needed.

The trouble I have is when I have the preview pane turned on and I am working in a folder that contains some of these online-only files. DOpus will [presumably] try to fetch the file from Dropbox in order to populate the preview pane, but something goes awry and then it just hangs. I usually have to force-close

This issue, of course, never happens with locally stored files.

My workaround is to toggle the preview-pane off when I'm in folders that contain "online-only" files, but it would be nice if DOpus detected this state and didn't seek to create a preview.

Also for anyone who is familiar with selective sync and Dropbox, is there a quick command to download all files in a folder to work on them locally?

Here's a screenshot from a folder that has a mix of online-only and local files. The online-only ones are denoted with the little cloud emblem and the green check denotes local.

Next time it happens, could you make some process snapshots so we can see what's blocking what?

It could be an issue with DropBox itself (we've other situations where DropBox deadlocks itself because it doesn't like too many threads making requests at once), but it could also be that Opus is doing something wrong which we might be able to fix.

Regarding the preview pane and offline files, we may add an option for that. We've always felt that if the preview pane is on it's because people want to view the files they select (else why waste the screen space, when it's a one-click toggle). But we understand some people like to leave it on all the time.

Yep I'd be glad to. It says in the guide that I shouldn't post them publicly. What would be the best way to get them to you?

Regarding the question of how to handle previews of "online-only" files, the issue that I have is that it's slow (and will occasionally hang/crash). Given how snappy OPUS is otherwise, my preference would be not to generate previews (to avoid the slowness), but I can definitely see that my preference wouldn't be universal. Perhaps just an option within the settings of whether or not to load previews of online-files would work for everyone?

As storage continues to shift to online hosting (and off of local device storage), it seems like this issue will become increasingly prevalent.

The guide says where to send them, near the end.

Just sent a dump file for your review!

Thanks for the snapshots!

Looking at those, it's always happening with .docx files, and it looks like Microsoft Word's preview handler has failed to open the file and Opus is waiting for it to close, but it isn't closing for some reason.

Unfortunately, the Word preview handler runs in its own process, so we can't see it in the snapshots. But it's probably outside our control anyway, as it's likely either the Word viewer is hanging or Dropbox is hanging.

Snapshots of the docsvw64.exe (or sometimes docsvw32.exe) and WinWord.exe processes might reveal where the fault lies, but would probably just mean you knew which big company to report the problem to and then they would ignore it. :smiley:

What happens when you open the same files in File Explorer's preview pane? Does it work there, or have the same issue? Or does it prevent previewing them entirely until they're stored locally?

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I'll see what happens w/File Explorer. Also, is there an alternative preview handler for .docx files that I could try?

There are the QuickView preview handlers but we’ve had mixed reports about whether they still work, and they are very expensive now.

My guess is the problem is more likely to be Dropbox than the preview handler, since cloud storage should be transparent to applications if it is functioning properly. (Should be. It never is. It’s the number one cause of strange delays and freezes these days, and all the different vendors seem to have different bugs.)

Yeah makes sense.

I don't actually need .docx previews at all in my workflow. Is there an option to turn off .docx previews altogether?

Preferences / Viewers / Plugins, configure the ActiveX + Preview + Office + Web plugin and turn off the Word preview handler within there.

OK excellent. I just turned it off.

I also noticed that "Microsoft PDF" was added as a preview handler for PDF and was changed to the default handler (from PDF-Xchange). Just wondering if this was a DOpus update thing or a Microsoft thing?

Microsoft. Although it's not just them. PDF viewers love to fight with each other over the file type; it's in their nature. :slight_smile:


I just wanted to chime in here and give an update. I thought that the issue stemmed particularly from online-only image files, but now that I have turned off previews for .docx and .xlsx (Word and Excel) files, the instability problem has seemed to evaporate!

For those of you out there that don't particularly need to see previews of these file types and are suffering from Dropbox "online-only" instability, I'd recommend this as a workaround-