A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Glad that sorted things for you. I have no idea why Excel behaves in this way, I too have experienced the same issue but have never found a definitive answer.
One day you'll find that the method I gave you doesn't work because as well as being text values there are also invisible characters; usually char 160, that stop this method converting them. I became so fed up with solving this on an ad hoc basis I now keep the macro below in my personal workbook to clean data before converting.
Sub CleanMe()
Dim c As Range
For Each c In Selection
If Not c.HasFormula Then
With c
.Value = WorksheetFunction.Trim(.Value)
.Value = Replace(.Value, Chr(160), "")
End With
End If
Next
End Sub