Created Unassigned: File corrupt [15261]

I have a weird bug where the Excel file is corrupt. I use EPPlus to open a template which is an xlsx file where I add data coming from a database and serve that modified file to the client. When I opening it, Excel crashes, starts in protected mode and an error message comes up saying the file is corrupt. It works alright if I try to open the unprocessed file though.

The weird thing is it crashes my Excel which is version 14.0.7116.5000 but not on my colleague's version (14.0.6123.5001) and we both have the 64 bits version of Office Professional Plus 2010.

And when my colleague saves under Excel, I am able to open the file he saved without problem... So I've tried to compare the file he saved with the one generated by EPPlus (by opening it as a Zip file) and found differences in the [Content_Types].xml file. And when I tried to replace the EPPlus generated file's [Content_Types].xml with my collegue's saved file [Content_Types].xml, I could then open the xlsx file without problem...

So it looks like the EPPlus generated [Content_Types].xml file is causing this error... You'll find in the attachments the EPPlus generated [Content_Types].xml and the Excel generated [Content_Types].xml