Created attachment 73054 [details]
test file produced with Microsoft Excel 2013 preview
The attached file was saved by the preview of Excel 2013 in the "strict" variant. Try to open it. LibreOffice does not detect this file format, but opens the dialog to choose a file type. If you select "Office Open XML" the file cannot be opened.
Operating System: Debian
Version: 3.5.4 release
This file doesn't open in in LibreOffice 126.96.36.199.
It's type is not detected. When checking Office Open XML SpreadSheet it shows "Input/Ouput error"
This file can't be opened in 188.8.131.52 either. LibO tries to repair but fails.
Setting this to NOTABUG. The file is plain broken. If I try opening it with any LO version I get Input/Output Error.
But if I try opening the file with Word 2011 on OSX 10.9 Excel will not open the file as well with the info that the file format is invalid.
So if Excel cannot open this, the behavior is not a bug but expected.
I believe the point is that this kind of .xlsx file, made by Excel 2013 (if requested), is in the *new* MS format OOXML strict variant that old Excel (pre 2013?) cannot read and LO cannot yet read. As this format has become an ISO standard, and as people start to use the strict variant for standards/compatibility reasons, it would be very useful for LO to support it (though also encourage use of ODF).
Bug 56048 is the same thing for the new .docx format and has just been made highest priority.
Philip, thanks a lot for clarifying what's requested here. So MS Office 2013 is needed for testing this I guess. That's not available on OSX (thanks MS for that).
Setting to NEW and sorry for closing this to quickly.
Should be fixed, thanks to Markus (see commit: http://cgit.freedesktop.org/libreoffice/core/commit/?id=e34870c2396db160c15e3e9bbf3efabf55ee2839 and related in the same date-range).
@Markus: please feel free to correct me if I'm wrong :-).
Attached documents opens correctly, tested using Windows 8.1 with LibreOffice Version: 184.108.40.206.alpha0+
Build ID: 90dd4320de6ace24e464979630a2c9fbab35f64b
TinderBox: Win-x86@39, Branch:master, Time: 2014-03-19_00:22:53
Also available in the upcoming 4.2.3