property Column.Width as Long

Retrieves or sets the column's width.

TypeDescription
Long A long expression that indicates the column's width in pixels.

The Width property specifies the column's width in pixels. Use the Visible property to hide a column. 

To change the column width for all columns, you can use the following sample , by handling the AddColumn event:

Private Sub ExplorerTree1_AddColumn(ByVal Group As EXPLORERTREELibCtl.IGroup, ByVal Column As EXPLORERTREELibCtl.IColumn)
    Column.Width = 196
End Sub