Press Alt+F11 to activate the Visual Basic Editor.
Select Insert > Module.
Copy the following code into the code module:
Function ExtractText(s As String) As String
Dim i As Long
For i = 1 To Len(s)
If Not Mid(s, i, 1) Like "[0-9]" Then
ExtractText = ExtractText & Mid(s, i, 1)
End If
Next i
End Function
Press Alt+F4 to close the Visual Basic Editor.
Usage:
Let's say Ash2ra3f4 is in cell A1.
In another cell, enter the formula =ExtractText(A1)
Make sure that you save the workbook as a macro-enabled workbook (.xlsm) and that you allow macros when you open it.