VBA Excel; Rows.Count not counting all rows

I’m trying to run a script that inserts a number in to a cell based on the cell’s color; if the color is red, then insert the # 1. The spread sheet has 380 rows but the script stops running (inserting 1’s) at row 346. Script below:

Sub InsertOne()

Dim endRow As Long
Dim colorD As Range
Dim Cell As Range


endRow = Sheets(1).Cells(Sheets(1).Rows.Count, "C").End(xlUp).Row

'Ensure ending row is at least Row 2 

If endRow < 2 Then
  endRow = 2
End If

Set colorD = Range("F2", Range("F" & Rows.Count).End(xlUp))

'Loop through each cell in Column D

For Each Cell In colorD

    If Cell.Interior.ColorIndex = 3 Then 

        Cell.Value = 1

    End If

Next Cell

End Sub 

Sub InsertOne()

    Dim endRow As Long
    Dim colorD As Range
    Dim Cell As Range


    endRow = Sheets(1).Cells(Sheets(1).Rows.Count, "C").End(xlUp).Row

    'Ensure ending row is at least Row 2

    If endRow < 2 Then
        endRow = 2
    End If

    Set colorD = Range("F2:F" & endRow)

    'Loop through each cell in Column D

    For Each Cell In colorD

        If Cell.Interior.ColorIndex = 3 Then

            Cell.Value = 1

        End If

    Next Cell

End Sub

Tags: excel-vbaexcel, vba