To amend your original:
Sub textTonumber()Dim ws As Worksheet
Set ws = Worksheets("qry_creategantt")
ws.Range("I2", ws.Range("I2").End(xlDown)).TextToColumns Destination:=ws.Range("I2"), DataType:=xlDelimited, _
TextQualifier:=xlTextQualifierDoubleQuote, ConsecutiveDelimiter:=False, Tab:=True, _
Semicolon:=False, Comma:=False, Other:=False, FieldInfo:=Array(1, 1), TrailingMinusNumbers:=True
End Sub
or skip the variable:
Sub textTonumber()
With Worksheets("qry_creategantt")
.Range("I2", .Range("I2").End(xlDown)).TextToColumns Destination:=.Range("I2"), DataType:=xlDelimited, _
TextQualifier:=xlTextQualifierDoubleQuote, ConsecutiveDelimiter:=False, Tab:=True, _
Semicolon:=False, Comma:=False, Other:=False, FieldInfo:=Array(1, 1), TrailingMinusNumbers:=True
End With
End Sub