This error happens at the db = client.Database() line of code below:

    Dim NewSearch As LFSearch
        Dim AllHits As ILFCollection
        Dim Hit As LFSearchHit
        Dim EntryHit As ILFEntry
        Dim Doc As LFDocument
        Dim strPathName As String = ""
        Dim strParentFolder As String = ""
        Dim db As LFDatabase
        Dim client As New Object
        Dim ClonedConn As New LFConnection
        Dim LFImageEnable As New LFIMAGEENABLE80Lib.ImageEnable
        Dim bOpen As Boolean

        ' Checks whether the Laserfiche client is open.
        bOpen = CBool(LFImageEnable.IsLaserFicheOpen)
        If Not bOpen Then
            LFImageEnable.LoadLaserFiche(True)
            'Login to Laserfiche
            LFImageEnable.Login(DATABASE_NAME, LF_SERVER, USER_NAME, USER_PASSWORD, 2)
        Else
            Try
                'Work-around to avoid error 6000 with every other scan 
                LFImageEnable.Logout()
                LFImageEnable.Login(DATABASE_NAME, LF_SERVER, USER_NAME, USER_PASSWORD, 2)
            Catch ex As Exception
                Select Case ex.Message
                    Case "External component has thrown an exception."
                        LFImageEnable.Login(DATABASE_NAME, LF_SERVER, USER_NAME, USER_PASSWORD, 2)
                    Case Else
                        Throw New Exception(ex.Message)
                End Select
            End Try
        End If

        'Set the integration folder
        INTEGRATION_FOLDER = Microsoft.Dexterity.Applications.Dynamics.Globals.IntercompanyId

        'Access an open Laserfiche client and clone connetion

        Try
            client = GetObject(Nothing, "LFClient.Document")
        Catch ex As Exception
            Throw New Exception("The Laserfiche client is not open.")
        End Try

        'Get its connection 
        Try
            db = client.Database()
        Catch ex As Exception
            Throw New Exception("You are not logged into a database.")
        End Try