The Excel-2003 tag is used for referencing the Excel Version 2003 spreadsheet application from Microsoft. The version independent Tag is "excel". If your question is about VBA then also tag it VBA. If it is about an Excel formula or worksheet function, then tag it excel-formula or worksheet-function.
Excel 2003 is the 11th version of Microsoft's commercial spreadsheet program, and the last to feature the original toolbar interface.
Very few changes were made from Excel 2002 to 2003 (see below for link). Built-in XML support and List features were added.
This tag is used for questions specific to the 2003 version of the program. However, it is usually used in tandem with other tags, to let SO users know what your question is about. If your question is about VBA then also tag it excel-vba. If it is about an Excel formula, tag it excel-formula or worksheet-function. Questions about addins for Excel 2003 should be tagged excel-addins.
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