Error message when opening an Excel 97-2003 worksheet in Excel 365

[CharlieAJ9N]

I have spreadsheets in Excel 97-2003 Worksheet format.  When I try to open the file in Excel 365 I immediately get an error message:

Name Conflict

Name cannot be the same as a built-in name

Old name Print_Area

New name 

If I give it a new name, I do get into the file but I have no idea where this might be inside the file.

Why am I getting this error message?  Thanks for the help.

[#2]

@CharlieAJ9N 

Newer versions of Excel reserve the name Print_Area for when you specify the area of a worksheet to be printed (Page Layout tab of the ribbon > Print Area > Set Print Area).

In older versions this name was not reserved, so you could give any range this name.

To see where the (renamed) range is, click Name Manager on the Formulas tab of the ribbon.

[#3]

@Hans Vogelaar 

Thanks Hans for the explanation.  This one caught be by surprise.  I wish the error message had a much better explanation.

CharlieAJ9N