Reference last column in worksheet

Greetings,

I'm trying to dynamically reference the last column using

Columns().Select

. I can't seem to figure out how to convert the column reference from a number to a letter.

Sub RestorePivtTable()
Set ws = ThisWorkbook.Sheets("sheet1")
llc = ws.Cells(2, ws.Columns.count).End(xlToLeft).Column
    Columns("E:" & llc.address & "").Select
    Selection.ClearFormats
End Sub

These other methods have failed as well.

'Columns("1:" & lc.Address & "").Select
    'Columns(1, llc).Select
    'Range(Columns(1), Columns(llc)).Select
    'Columns("E:" & Cells(3, llc).Address & "").Select
    'Range("1:" & Cells(3, lc).Address & "").Select
    'Range(Cells(1, 1).Address, Cells(3, llc).Address).Select
    'Columns("" & llc & ":" & llc & "").Select

Greetings,

I have a function which converts a column number reference to a letter reference. However, when I try to pass that converted column letter reference using

Columns("E:" & myCol).Select

or

Columns("E:" & myCol & "").Select

, I receive a "Run-time error '1004'." I've tested the function using:

Sub Test2()
MsgBox GetColumnLetter(100)
End Sub

and it correctly displays the column letter.

Below is my macro and function:

Sub Test1()
Dim lc As Long
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets("sheet1")
lc = ws.Cells(3, ws.Columns.count).End(xlToLeft).Column
myCol = GetColumnLetter(lc)
    'Columns("E:" & myCol & "").Select
    'Columns("E:" & myCol).Select
    Selection.ClearFormats
End Sub

Function GetColumnLetter(colNum As Long) As String
    'http://stackoverflow.com/questions/16941083/use-last-column-for-a-rangeflastcolumn
    Dim vArr
    vArr = Split(Cells(1, colNum).Address(True, False), "$")
    GetColumnLetter = vArr(0)
End Function

why not use a column number instead of a letter
something like this

Sub ttt()
Dim clm As Long
clm = Cells(1, Columns.Count).End(xlToLeft).Column
Columns(clm).Select
End Sub

The function and macro work correctly. I made the mistake of having put them in a worksheet Microsoft excel object. Thank you very much everyone for your help.