Error checking for table fields null value constraint

Hi all. I want to check for not null value constraint for all tables in database . I tried the following but when i run it i get the following error:

Compile error:
Invalid Next control variable reference

I be happy if some one one help me fix this error.if i remove the bold lines the program workes well but it does not put not null for table fileds that requries value.

picture of the output without the bold part

http://i5.photobucket.com/albums/y18...07/notnull.jpg

Code:

Option Compare Database ''This module displays field name and type in a massage box Function ShowFields(pTable As String) As String Dim db As Database Dim rs As Recordset Dim I As Integer ''Dim j As Integer Dim n As Integer ''Dim NL As String Dim strHold As String, ST As String ''Dim x As Variant ''NL = Chr(13) & Chr(10) ' Define newline. Set db = CurrentDb Set rs = db.OpenRecordset(pTable) n = rs.Fields.Count ReDim x(n - 1, 1) As String '''ST = "Create Table " & pTable & vbCrLf ''adding Create table and table name to statement ST = "Create Table " & pTable & vbCrLf & "(" For I = 0 To (n - 1) For Each fld In tbl.Fields ST = ST & rs.Fields(I).Name & " " & FieldType(rs.Fields(I).Type) & "," & vbCrLf If fld.Required = True Then ST = ST & " NOT NULL" & " " Else ST = ST End If Next I rs.Close db.Close Set db = Nothing ShowFields = ST '' returns the fields name to main function End Function

on click even code

Code:

For Each T In db.TableDefs '''Skip the system tables If Left(T.Name, 4) <> "MSys" Then ''' this line determines the primary key of the table ''' by calling GetPk function from module pk = Left(GetPK(T, db), InStr(1, GetPK(T, db), "<-") - 1) cont = cont & ShowFields(T.Name) & vbCrLf & " primary key " & "(" & pk & ")" & vbCrLf & ")" & vbCrLf End If Next T ''' This line of code post the generated table statment to a massage box MsgBox cont