How to change file extensions from xls to xlsx

Are you looking for an option to programmatically change a file extension? What is the use case? Why can't you upload a file with the other extension?

Create a custom smart service to work around the inability to upload a new version of an existing file that has a different file extension.

@sathya - we actually receive the file in xls format and we are currently changing it manually to xlsx. there is business constraint (it would cost for sending in xlsx) on getting the file with xlsx format.
@jorgea - we are looking into that option of CSS parallely.
Thanks for you inputs.

Did you get the solution on this?

I have the same challenge. The shared component for writing to excel files insists on a .xlsx extension. I am however writing a file which contains macros and is saves the file as filename.xls. The problem is, that the user needs to save it as xlsm.

Hi Richard,
I'm using macros in excel template. And generated file is in .xlsx format. I don't want user to save it as .xlsm/xltm manually.
Did you find any solution on this?

Thanks in advance.