Hello from Steved

I am a beginner in programming
I am getting a compile error:
Block IF without EndIf

What is needed for the below please.

Sub ProcessBooks()
Dim FName As String
Dim FoundCell As Range
Dim WB As Workbook
Dim mySht As Worksheet
Dim myBook As Workbook
Dim ReplaceWith As String
Dim ToReplace As String
Dim cnt As Long, num As Long, num1 As Long
Dim ans As Variant
Dim bFirst As Boolean

ChDrive "C:"
ChDir "C:\Wtt"
FName = Dir("*.xls")
Do Until FName = ""
Set WB = Workbooks.Open(FName)
FName = Dir()
Loop
bFirst = True
Do While True
cnt = 0
If Not bFirst Then
ans = MsgBox("Go again", vbYesNo)
If ans = vbNo Then Exit Sub
End If
bFirst = False
ToReplace = Application.InputBox("What value to replace?")
ReplaceWith = Application.InputBox("Replace '" & _
ToReplace & "' with what other value?")
If ToReplace = "" Then Exit Do
For Each myBook In Application.Workbooks
If myBook.Name < ThisWorkbook.Name Then
For Each mySht In myBook.Worksheets
msg = " in Book: " & myBook.Name & " Sheet: " &
mySht.Name
If MsgBox("OK to replace" & msg, vbYesNo) = vbYes Then
num = Application.CountIf(mySht.UsedRange, ToReplace)
mySht.Cells.Replace _
ToReplace, ReplaceWith, _
xlWhole
num1 = Application.CountIf(mySht.UsedRange, ToReplace)
If num 0 Then
cnt = cnt + 1
End If
If num1 < 0 And num 0 Then
MsgBox "Problems with " & mySht.Name
mySht
myBook
MsgBox cnt & " sheets were changed"
myBook.Close SaveChanges:=True

End Sub