I'm willing to stand corrected ... but I don't think I get it yet. I just selected and uploaded two workbooks, one named x.xls and the other x.xlsx. I selected them both simply by clicking on them in the File-Upload dialog; I didn't type anything additional in the filename text box. When I open the first, it opens normally in my Excel 2010 without complaint. When I click on the second, I get this message: "The file you are trying to open, 'x.xlsx-1.XLS', is in a different format than the one specified by the file extension...." and so on. When I open that one anyway and then offer to save it, it wants to save it as "Copy of x.xlsx-1.xlsx".

I may be mistaken about what MSOfficeForums.com is doing, but it seems to me it's surely doing something that isn't completely correct.

Attached Files

	x.xls (153.0 KB, 12 views)
	x.xlsx (11.9 KB, 14 views)

Things are exactly the same for me as for Bob. When I open files on other forums ( EF, CC, MrE,Ozgrid, Excelguru) the files always open normally.
Very strange

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