MicrosoftВ® Office ExcelВ® 2007: Data Analysis and Business Modeling (Bpg -- Other)

Excel does not allow you to use the letters r and c as range names.

If you use Create from Selection to create a range name, and your name contains spaces, Excel inserts an underscore (_) to fill in the spaces. For example, the name Product 1 is created as Product_1.

Range names cannot begin with numbers or look like a cell reference. For example, 3Q and A4 are not allowed as range names. Because Excel 2007 has over 16,000 columns, a range name such as cat1 would not be permitted because there is a cell CAT1. If you try and name a cell CAT1, Excel tells you the name is invalid. Probably your best bet is to name the cell cat1_.

The only symbols allowed in range names are periods (.) and underscores (_).