getting pop up message in saving xlsm as files are in xls with macros

I have an issue, recieved a workbook with format .xls 97 -2003 , in opening excel warns me of macros which I enabled, there are 3 sheets group ready for printing .

But doing some work and inserting my macros and saved to xlsm.

I got this message as attached Can anyone explain me what it is ,it's the first time I got such message , and how to get rid of it

That reference could be interpreted by Excel (2007 and later) as meaning the cell RF1. This wouldn't have been a problem in earlier versions of Excel (i.e. those that used .xls extension), as there were only 256 columns available, so cell references only went up to column IV, but later versions have column references which go up to XFD. The warning tells you that instead of using the name rf1, this has been changed to _rf1 (i.e. with an underscore in front of it), and that you may need to make manual changes yourself in any text values that make use of the original name, or any macros which make use of it, because these will not be changed automatically.

Hope this helps.

Pete

Hi Richard & Pete

Thanks for explanation, now I understand the why

Regards

Jean