Searching keywords in title - vba

Question

Im using the below code for seacrhing a set of keywords in a cell which has title. While running the code im getting "Run Time error 13" Type mismatch on b = cell.Value line.
Application.ScreenUpdating = False
Dim col As Range, cell1 As Range, a As String, b As String, i As Integer
Set col = Range("KW[KW1]")
Dim target, cell As Range
Sheets("Data").Select
Set target = Range(Range("B1"), Range("B65536").End(xlUp))
Dim term, tag As String
For Each cell1 In col
a = cell1.Value
term = a
tag = a
For Each cell In target
b = cell.Value
' If InStr(1, " " & cell & " ", " " & term & " ", 1) Then
If Module1.ExactWordInString(b, a) Then
For i = 1 To 15
If cell.Offset(0, i).Value = "" Then
cell.Offset(0, i).Value = tag
Exit For
End If
Next i
End If
Next cell
Next cell1
Application.ScreenUpdating = True
However its running perfectly if we have 1000 tiltes in a column, but i want to run this code for a massive range upto 50,000 to 200,000. Please help me.

Answer 1

Try this, you didn't declare target as a range, might be it.
BTW, when you compare string VBA is case sensitive, so try to use Lcase() if you only want to compare content!
Application.ScreenUpdating = False
Dim target As Range, cell As Range
Dim term As String, tag As String
Dim col As Range, cell1 As Range, a As String, b As String, i As Integer
Sheets("Data").Select
Set col = Range("KW[KW1]")
Set target = Range(Range("B1"), Range("B65536").End(xlUp))
For Each cell1 In col
a = Cstr(cell1.Value)
term = a
tag = a
For Each cell In target
b = Cstr(cell.Value)
'If InStr(1, " " & cell & " ", " " & term & " ", 1) Then
If Module1.ExactWordInString(b, a) Then
For i = 1 To 15
If cell.Offset(0, i).Value = "" Then
cell.Offset(0, i).Value = tag
Exit For
End If
Next i
End If
Next cell
Next cell1
Application.ScreenUpdating = True