XlYesNoGuess Enumeration [Excel 2007 Developer Reference]

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XlYesNoGuess Enumeration
Specifies whether or not the first row contains headers. Cannot be used when sorting PivotTable reports.

Version Information
 Version Added:  Excel 2007

NameValueDescription
xlGuess0Excel determines whether there is a header, and where it is, if there is one.
xlNo2Default. The entire range should be sorted.
xlYes1The entire range should not be sorted.