Q: Can't open any iCloud documents on mac

I have the same issue. I can't open any of my Pages or Numbers files that are stored in iCloud from my El Capitain Mac.

The same files open fine on my iPhone.

If I try to drag the files out of the iCloud folder to my desktop I get a -36 error, which is a Mac OS disk read / write error.

I have a similar problem withe sharing my Numbers and Pages material to Icloud.  Thefile shows up in Icloud but willnot open it.  The message is that the Index.xml file is missing.  How so I include this file?

I am running the latest versions of El Capitan, iOS 9, updated Pages, Numbers, etc.

I cannot open any document stored in iCloud from my Mac. They open fine in a web browser, iPhone, etc.

Last night I tried disabling / re-enabling iCloud on my Mac. It re-downloaded everything, but I still had the same problem. Nothing will open.

Logging out of my user account on the Mac or rebooting seems to be the only thing that temporarily fixes this problem. It is so annoying.

I found this in a different thread but I have not tried it yet so I can't verify if it works or not..

Step-by-step:

1. renamed .numbers-tef file to .pdf;

2. control cliked - then - Show Package Contents

3. double clicked index.xml.gz - index.xml has been created!

4. renamed back .pdf to .numbers

5. double cliked file and Bingo! Numbers opened the file.

I spent a lot of time digging into this as it is extremely annoying when this problem occurs, but in the end I have found that a simple reboot will solve this problem and allow access to the iCloud drive files and they can then be opened from the Mac OS Pages, Numbers, Preview, etc..

I wish I could come up with a permanent solution as this is obviously not how it's supposed to work.

Good luck and thank you for your courage.

I have exactly the same issue. Unable to open MS Office, Numbers, Pages and other "office files" stored in iCloud from my MBP (OS X 10.11.5).

Works fine to open from iPhone and web. Not possible to copy the file to a local disk, but I can mail the file to myself, open it and then save it back to iCloud (overwriting the existing file).

Have not tried rebooting the machine, but if this is the best solution to get this working, I will cancel my iCloud subscription and revert back to Dropbox, a solution that works perfectly flawless.

I can not contribute much towards the solution of the problem. But I can say that it happens over and over and over again.

Only happens on my Macbook air. I can open it on iPhone or Macbook pro.

If a reboot fixes the problem but only for a short time then you have some thing corrupted with your macOS install. Search the web for "how do I do a clean install of mac os. This should fix the problem for good.On newer OS X like El Capitan you can install right over your current installation.

I actually got someone from Apple on the phone a month ago but ... he couldn't help me.  Basically had me reboot even though I told him that only temporarily solves the issue.  He told me he would follow up in a few days but the problem had not yet occurred so the ticket was closed. 

Oddly, I can open Microsoft Office documents and ZIP files.  But not Pages, Number, JPGs, PDFs, text files etc. 

Ok. Now I can't open Microsoft Office documents either.

Apple support is having me remove AV although the AV is launched manually as needed.  I think next they will ask me to remove ALL my software and rebuild the Mac.

I have the same issue, but I use iCloud on one device only so it's no sync-problem (MacBook Pro (Retina, 13-inch, Late 2013), 10.11.6 (15G31))

And actually I can open the files with an application that is not an Apple one.

For example, happens a lot with TextEdit files (plain and simple .txt): whenever I cannot open them, I open with Brackets, no issue.

Not a fix, but by moving files out of iCloud onto, say desktop, the file then opens fine. Just have to remember to move it back to iCloud when saving.