.xls files suddenly won't open Since yesterday my .xls files will not open in Office for Mac 2011. They have always done so till then. I can still open .xlxs files. The default 'open with' option is still the Microsoft Excel.app. I haven't (not aware of) having made any software updates yesterday. The message I get is that the file c'cannot be accessed' because it 'may be read-only, or you may be trying to access a read-only location. Or, the server the document is stored on may not be responding'.

But, it is happening with ALL .xls files,whether on my own drive that I have no problem accessing for other files, on things just emailed to me, or as downloads from a Skydrive facility.

Any ideas? thanks
Change the name of your main hard drive to something with only letters and optionally spaces.

That usually solves this issue with Microsoft's assumptions about characters in path names.