This is just a small Database Schema Utility Class.
Code:
Option Strict On
Option Explicit On

Imports System.Data.OleDb

'This Code is given freely with no limitations on usage either personal or business.
'Code is provided "As Is" and has no warranties or guarantees associated with it.
'This is designed for versions of access prior to 2007, 2007 or later will need to modify 
'at minimum the connection string.


Public Class AccessSchemaUtility

    'Global OledDBConnection
    Private globCN As OleDbConnection

    Protected Friend Function CreateNewConnection(ByVal FileName As String) As Boolean
        Dim cnStr As String = String.Empty
        Dim dbloc As String = String.Empty

        Try
            'If the database string stored in setting exists use it
            'Else find the database.  Once found setting gets changed.
            If System.IO.File.Exists(FileName) = False Then
                dbloc = "C:\New Folder\Air Enterprises\AE_Data.mdb"

            ElseIf System.IO.File.Exists(dbloc) = False AndAlso System.IO.File.Exists(FileName) = False Then
                'If file cannot be found then use an open file dialogue to find an appropriate database.   
                Dim ofd As New OpenFileDialog
                With ofd
                    .CheckFileExists = True
                    .Multiselect = False
                    .DefaultExt = ".mdb"
                    .Filter = "Database Files(*.mdb)|*.mdb"
                    .InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
                    .Title = "Find Database"
                    .ShowDialog()
                    dbloc = .FileName
                End With
            End If

            'Setup the connection string
            cnStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & dbloc & ";"

            'If connection does not exist or is not currently open then create new connection
            If IsNothing(globCN) = True Then
                globCN = New OleDbConnection(cnStr)
                globCN.Open()
            End If

            Return True
        Catch ex As Exception
            MessageBox.Show(Err.Number & ": " & Err.Description)
            Return False
        End Try
    End Function

    Protected Friend Function TestConnection(ByVal cn As OleDbConnection) As Boolean
        'This is just a simple function to check if your database connection is open
        Try
            Select Case cn.State
                Case ConnectionState.Broken
                    Return False
                Case ConnectionState.Closed
                    Return False
                Case ConnectionState.Connecting
                    Return True
                Case ConnectionState.Executing
                    Return True
                Case ConnectionState.Fetching
                    Return True
                Case ConnectionState.Open
                    Return True
            End Select
        Catch ex As Exception
            Return False
        End Try
    End Function

    Protected Friend Sub DisconnectFromDB()
        Try
            'Destroys the connection.
            If Not IsNothing(globCN) Then
                globCN.Close()
                globCN.Dispose()
                globCN = Nothing
            End If
        Catch ex As Exception
            MessageBox.Show("Error Closing Database Connection " & Err.Number & ": " & Err.Description)
        End Try
    End Sub

    Protected Friend Sub AddColumnToDB(ByVal DBName As String, ByVal TableName As String, ByVal ColumnName As String, ByVal ColumnType As String)
        Dim cmd As OleDbCommand = Nothing
        Dim SelStr As String = String.Empty
        Dim dt As New DataTable

        Try
            If CreateNewConnection(DBName) = True Then

                'get list of fields in the access table
                dt = GetAccessTableColumnList(DBName, TableName)

                'IF nothing is returned then there was most likely an error and need to exit.
                If dt Is Nothing Then
                    Throw New Exception("Unable to find Column List for table " & TableName & ".")
                End If

                'Check for the specified field name, if found simply exit sub
                'This *IS* Case Sensitive.....
                For i As Integer = 0 To dt.Rows.Count - 1
                    If dt.Rows(i).Item(3).ToString = ColumnName Then
                        Exit Sub
                    End If
                Next

                'If it gets to this point then the field is not in the table and needs to be added
                cmd = New OleDbCommand

                SelStr = "ALTER Table " & TableName & " ADD COLUMN " & ColumnName & " " & ColumnType

                cmd.CommandType = CommandType.Text
                cmd.CommandText = SelStr
                cmd.Connection = globCN

                cmd.ExecuteNonQuery()
            Else
                MessageBox.Show("Cannot Connect to Database")
            End If
        Catch ex As Exception
            MessageBox.Show("Error Adding Column to Database " & Err.Number & ": " & Err.Description)
        Finally
            'cleanup objects
            If cmd IsNot Nothing Then cmd.Dispose()
            If dt IsNot Nothing Then dt.Dispose()

            'Close database connection
            DisconnectFromDB()
        End Try
    End Sub

    Protected Friend Function GetAccessTableList(ByVal DBFile As String) As DataTable
        Dim dt As New DataTable
        Try
            If CreateNewConnection(DBFile) = False Then
                Return Nothing
            Else
                dt = globCN.GetSchema("Tables")
                Return dt
            End If
        Catch ex As Exception
            MessageBox.Show("Error getting Access Table Schema: " & Err.Number & ": " & Err.Description, "Error Getting Access Table Schema")
            Return Nothing
        End Try
    End Function

    Protected Friend Function GetAccessTableColumnList(ByVal DBName As String, ByVal TableName As String) As DataTable
        Try
            If CreateNewConnection(DBName) = True Then
                Dim dt_field As DataTable = globCN.GetOleDbSchemaTable( _
                                OleDb.OleDbSchemaGuid.Columns, _
                                New Object() {Nothing, Nothing, TableName})

                Return dt_field
            Else
                Return Nothing
            End If
        Catch ex As Exception
            MessageBox.Show("Error getting Access Table Schema: " & Err.Number & ": " & Err.Description, "Error Getting Access Table Schema")
            Return Nothing
        End Try
    End Function

End Class