Excel iterate through worksheets

Question

I have a workbook with many sheets and into some I need to enter a value if the preceding cell matches a given string.

My code works for the sheets I need it to but

Answer 1

You need to check that the 2 ranges intersect:

Sub AllOnePool()
    Dim myStr As String
    Dim myPool As String
    Dim sh As Worksheet
    Dim cel As Range
    Dim xIng As Range

    myStr = InputBox(Prompt:="Input the Target Serial Number: i.e. 93127")
    myPool = InputBox(Prompt:="Input the Pool to Use: ")

    For Each sh In ActiveWorkbook.Worksheets
        With sh
            Set xIng = Intersect(.UsedRange, .Range("F:F"))
            If Not xIng Is Nothing Then
                For Each cel In xIng
                    If cel.Text = myStr Then cel.Offset(0, 1) = myPool
                Next
            End If
        End With
    Next
End Sub