This is a very very strange issue. I have quite a large excel file (the contents of which I cannot discuss as it is sensitive data) that is a .xlsx and IS a valid excel file. This is a very very strange issue. I have quite
This is a very very strange issue. I have quite a large excel file (the contents of which I cannot discuss as it is sensitive data) that is a .xlsx and IS a valid excel file. This is a very very strange issue. I have quite