Why would you want "white" borders? Why not no borders?
Code:
Sub ScratchMacro()
'A basic Word macro coded by Greg Maxey
Dim oRng As Word.Range
Dim oTbl As Word.Table
Set oRng = ActiveDocument.Range
oRng.Start = ActiveDocument.Bookmarks("StartHere").Range.Start
For Each oTbl In oRng.Tables
With oTbl
.Borders(wdBorderLeft).LineStyle = wdLineStyleNone
.Borders(wdBorderRight).LineStyle = wdLineStyleNone
.Borders(wdBorderTop).LineStyle = wdLineStyleNone
.Borders(wdBorderBottom).LineStyle = wdLineStyleNone
.Borders(wdBorderHorizontal).LineStyle = wdLineStyleNone
.Borders(wdBorderVertical).LineStyle = wdLineStyleNone
.Borders(wdBorderDiagonalDown).LineStyle = wdLineStyleNone
.Borders(wdBorderDiagonalUp).LineStyle = wdLineStyleNone
End With
Next oTbl
lbl_Exit:
Exit Sub
End Sub