Open xml sdk for excel 2003

Only date and number values are autofitted :-( quote: "... We do not autofit textual values"

http://msdn.microsoft.com/en-us/library/aa140066.aspx#odc_xmlss_ss:column

Another possibility, (which I used), is to use the HYPERLINK formula for Excel. I needed to create individual hyperlinks in each cell, yet the cells had to display different text, (I had to display tracking numbers in the cells yet have a hyperlink for each tracking number to the carrier's site and had to handle multiple carriers).

Once I instantiated an individual cell, the formula was applied in this manner to each cell (there are undoubtedly numerous way):

// ...
Cell cell1 = new Cell(){ CellReference = "A1", StyleIndex = (UInt32Value)1U, DataType = CellValues.InlineString };
CellValue cellValue1 = new CellValue();

CellFormula cellFormula1 = new CellFormula() { Space = SpaceProcessingModeValues.Preserve };
cellFormula1.Text = @"HYPERLINK(""http://www.theclash.com"", ""Radio Clash"")";
cellValue1.Text = "Radio Clash";
cell1.Append(cellFormula1);
cell1.Append(cellValue1);
// append cell, etc.

In this way, I was able to create individual hyperlinks and text for each cell. By the way, the links will appear with the default font color unless you reference a style with blue font.

Hope this helps.