Excel file in SkyDrive has permissions errors in Web app, but can be downloaded/re-uploaded

I am a member of a SkyDrive group and I've stored an .xls file in SkyDrive that I've been editing with Microsoft Office for the Mac 2011. I can:

(at least in Firefox; Chrome won't load the aging SharePoint Browser Plugin) open the file from SkyDrive in Mac Excel (via right-click "Open in Excel") and save the results back just fine.
I can right-click and Download fine.
I can right-click and "Open in Excel Web App" fine.

This is all great, and pretty nifty integration.

However, if I simply left-click on it, I get to a page that says "This item might not exist or is no longer available."

The network requests I get include:

https://skydrive.live.com/edit.aspx?cid=000989A33CDDFC1D&group=1&resid=989A33CDDFC1D%21899&app=Excel (returns 200 OK)
https://skydrive.live.com/convert.aspx?resid=989A33CDDFC1D%21899&id=documents&group=1&canary=sAfZCmB%2f7PhtEq8aGAwC3qaKdVSdk6Btwsrzk7sduNw%3d4 (and get a 404 not found)

What is supposed to happen when I click on this item? Why does it report the error?

Thanks,

Nathan Herring

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