Find sometimes generates Run time error 91 - excel

Question

I have a data table with column headings. I have a list of column headings that I don't want.
I want to delete the unwanted column headings no matter where they are in the worksheet and the ability for users to add other columns to delete.
I get
run time 91 error
on this line: ws.Rows("1:1").Select.Find(T).EntireColumn.Delete
Sometimes I will get an error in the first loop of the code, sometimes it will be part way through.
I have looked at other posts but the problems have not be related enough for me to problem solve my way through. I tried reading some articles on defining objects. I have been using the msgbox command to make sure the code is finding the values and that seems to be working all the time but it breaks down at the Find command.
Sub DeleteBadHeaders2()
Dim FirstHeading As Range
Set FirstHeading = Worksheets("Headings_To_Delete").Range("a2")
'Worksheet that has all the column headings I want deleted
Dim x As Integer
'x is for the do while loop to individually highlight each cell
Dim y As Long
y = Worksheets("Headings_To_Delete").Range("A:A").Cells.SpecialCells(xlCellTypeConstants).Count
'y acts as the upper bound to the headings to delete column for the while loop
Dim T As Variant
'T acts as a temporary value holder that will be used to delete the proper columns
Dim ws As Worksheet
Set ws = ActiveSheet
x = 0
Do While x < (y - 1)
Worksheets("Headings_To_Delete").Range("a2").Offset(x, 0).Interior.Color = RGB(224, 0, 0)
'Calling the rage as above fixes the active cell problem
Let T = Worksheets("Headings_To_Delete").Range("a2").Offset(x, 0).Value
'MsgBox T & " is found."
ws.Rows("1:1").Select.Find(T).EntireColumn.Select
'for testing switch the last part of the code to EntireColumn.Interior.Color = RGB(0, 225, 0)
x = x + 1
Loop
'The loop is highlighting the cells incrementally based on the first active cell until the upper limit of how many cells are in the column
End Sub

Answer 1

ws.Rows("1:1").Select.Find(T).EntireColumn.Select
should be
ws.Rows(1).Find(T).EntireColumn.Select 'Delete?
Typically though whenever using Find() it's a good idea to check you actually found anything, by testing the return value for Nothing before trying to do anything like Select or Delete.
Also a good idea to be explicit about some of the other parameters in Find, such as lookAt for example.
Something like this:
Sub DeleteBadHeaders()
Dim r As Long, lastRow As Long
Dim T As Variant
Dim ws As Worksheet, wsList As Worksheet, f As Range
Set ws = ActiveSheet
Set wsList = Worksheets("Headings_To_Delete")
lastRow = wsList.Cells(Rows.Count, 1).End(xlUp).Row 'last row
For r = 2 To lastRow
T = wsList.Cells(r, "A").Value
If Len(T) > 0 Then
Set f = ws.Rows(1).Find(what:=T, lookat:=xlWhole)
'check to see if the heading was found
If Not f Is Nothing Then
Debug.Print "Found header '" & T & "' at " & f.Address
f.EntireColumn.Interior.Color = vbRed '<< for testing
'f.EntireColumn.Delete '<< uncomment when done testing
End If 'was found
End If 'any heading
Next r 'next in list
End Sub