LF Connection Keeper
Version: 5.11 (2006-04-21)
Written by Lennart Franzén in 2006
© Lennart Franzén 2006, All rights reserved

LFCK main window

A powerful utility that manages any Network Connection

Measure network traffic, monitors the Internet State, manage DHCP and
keeps the internet connection alive on any network / internet connection!

Fully automatic Login / Logout management for Sweden's leading broadband suppliers

[ Register ] [ Downloads ] [ Support ]


  • Login and Logout

  • Login and Logout by one simple click of a button!
    LFCK supports Sweden's major broadband ISPs:
    • Telia HomeRun
    • Telia Broadband
    • Tele 2 Bredband
    • ComHem Internet Cable
    • One / Bahnhof Internet
    • Tiscali Bredband
  • DHCP Restart, Renew and Release

  • Manage your DHCP with a simple click of a button.
    LFCK can automatically renew your IP if the login fails multiple times
  • Keep Alive

  • To avoid getting disconnected all the time, LFCK has advanced keep alive features that works on any internet connection
  • Logout and release DHCP at shutdown

  • When LFCK shuts down it can automatically log you off and release your IP so other computers in your network can take it over
  • Auto Start

  • The program can start with windows and have you instantly connected and renew your IP upon startup
  • Run as Service

  • On later versions of Windows LFCK can be run as a service to have your internet connection enabled at all time
  • Network Traffic Monitor

  • Network activity is measured and shown in both a colored graph and the systray icon. Registered users can also display Average network traffic over a customizable time period. Network max values are customizable by the user
  • Systray Icon

  • The systray icon shows:
    • Network traffic; receiving and transmitting
    • Connection status; online, offline, unknown
    • Your current LAN IP
    • Your current WAN IP
  • Systray Menu

  • Clicking the right mouse button on the systray icon brings up a menu with quick access to key functions
  • Online Detection Logging (NEW!)

  • LFCK checks your actual online status every minute against servers on the web and can record a log file with dates and times when the connection was online and when it was offline. Perfect if you need hard evidence of a poor service by delivered your ISP
  • Online Detection Alert (NEW!)

  • LFCK checks your actual online status every minute against servers on the web and can inform you both audial and visual when you loose your internet connection and when it is back online
  • Registration

  • If you want to register LFCK there's an automated process available from the help menu and about dialog
    LFCK is freeware for private use if you don't want the extra features
  • Auto update

  • You can check for program updates manually or just let LFCK silently do this regularly to keep a news-ticker up to date in the main window
  • Themes

  • Change the systray icon With different theme-DLLs. Downloadable new themes from LFDomain
  • Logging

  • A log file with important events can be continuously written, with the last entries accessible from the main window
  • Easy Configuration

  • The configuration is easy to understand with helping tool-tips for the option you position the mouse over
  • Login server type Auto detection

  • LFCK can automatically determine which login server type you are using if you are not sure which to choose
  • Security

  • Your login information is stored in encrypted form on your computer and is not readable to anyone
  • Installation and Uninstallation

  • Setup Wizard will guide you through the installation process. Uninstall wizard will help you remove LFCK from your computer

    Unlock Additional Features

    Unlock LF Connection Keeper's additional features for registered users only!
    The following extra functionality will be made available when you register LFCK.

    Network Traffic Monitor

    • Max-, Min- and Average traffic is calculated and shown individually for transmitted and received data
    • A scale along with a grid dividing the diagram can be shown to make it easier to grasp the actual value
    • Average traffic over a user definable period of time can be displayed as another graph with it's own color in the traffic diagram
    • Both the history period (length of the network diagram in seconds) and average period (seconds over which to calculate the average speed) is customizable by the user

    Tray Icon

    • Average traffic over a user definable period of time can be shown in the tray icon instead of the realtime traffic
    • Your current WAN IP (your IP as seen from the outside) can be shown in the tray icon tool tip
    • Tray balloon that inform you if the connection goes on-/off-line

    Online Detection

    • Audiable alert when your internet connection goes on-/off-line by playing selected wav-files
    • Tray balloon in the systray that inform you if the connection goes on-/off-line
    • Popup message box alerts you when your internet connection goes on-/off-line
    • Log file over connection status and the time it changed can be saved to disc for statistical purposes


    • Change the appearance of LFCK to match your personality. All the colors in LFCK can easily be changed using the the build in color picker

    System Requirements

    LF Connection Keeper is programmed using MicrosoftFoundationClasses in Visual C++ for 32 bit windows.

    The software has been tested on

    • Windows 95
    • Windows 98, first and second edition
    • Windows Millennium
    • Windows NT4, SP2
    • Windows 2000, Professional and Server
    • Windows XP

    Version Release History

    v5.11 - 2006-04-21
      New Features:
      • Theme configuration now supports full color customization
      • Network graph split in two.
      • Network graph scale is now shown to the left along with a grid
      • Network status in graph with max / min / average for Transmitted and Received
      • Config tab for network traffic diagram
      • Config variable for network traffic diagram history time
      • Right-clicking on the traffic graph brings up it's configuration
      • Online detection can now alert via Tray Balloon in the system tray
      • Totally resizable main window
      • Tele2 login server update
      • Onlinestatus-log output cleaned up and a descriptive header was added upon file creation
      • Added a button in the registration process first step to open the registration preview page
      • LF Connection Keeper is now compiled with static MFC library to remove dependencies
      • .NET update: Code compatibility with new VisualStudio.NET
      • Network traffic graph average speed was not calculated according to the AverageTime, but the HistoryTime
      • Fixed bug in Message box rutines for online detection
      • Theme reader checks if load of DLL file failed
      • Theme path is now added to regkey along with filename
      • Fixed error in theme DLL array loading in config
    v5.10 - 2005-06-25
      New Features:
      • Added support for One.se loginservers after bahnhofs name change from bahnhof.se to one.se
      • Added Online Status Log - Logs the connection status every minute or upon online status change. User defined filepath (Registered user only)
      • Added Online Status Alert - Performs an audial and visual alert when the connection status changes (Registered user only)
      • Added Online Detection tab in config
      • Included a new theme; KBars
      • Log files are now updated in realtime with unbuffered writes so you no longer have to exit LFCK to read the last entries
      • WANIP address redirected to LFDomain.com for faster access (Registered user only)
      • Tabstop order in the registration process has been corrected
      • Phonenumber is no longer a required field to register
      • Didn't trigger relogin if onlinedetection reported offline when relogintimer was running
      • WAN IP urlbox didn't get enabled in the config
      • OnlineDetection array wasn't reset when changed in config

    v5.09 - 2005-03-21
      New Features:
      • Option to display average network traffic over a customizable time to main diagram
      • Option to display average network traffic over a customizable time in the tray icon
      • Option to show network graph scale (max values) in the diagram
      • Option to disable news ticker
      • Option to disable tray icon completely
      • Option to change the startup login delay
      • Option to manually set login server type (connection type)
      • Actual IsOnline check implemented. checks against reliable servers
      • Option to have IsOnline check performed every minute
      • Gets both the actual WAN IP (Internet address) and LAN IP (Local Network address)
      • Clicking the News Ticker displayes the message in a messagebox
      • Simpler config. No more activation of modules
      • Updated ComHem CON_STR_SESSION_ACTIVE
      • Add error values to the registration process messageboxes
      • Crucial registration variables are now trimmed from whitespaces before registration verifies the licensekey
      • Cancel button disabled when final registration check is performed
      • Added version number to main window caption
      • If LFCK started hidden and without trayicon, you couldn't open the LFCK window through another instance
      • "Next" button in registration wasn't enabled if the name entered was shorter than 3 characters

    v5.08 - 2005-01-15
      • Merged Telia and ComHem again due to incomplete loginserver information

    v5.07 - 2005-01-15
      New Features:
      • Always on Top (Registered user only)
      • Resizable main window: Full / Compact mode
      • Minimize main window to taskbar
      • Connection time online
      • Network activity graph footer suggested kilobit/s instead of kilobyte/s
      • Telia and ComHem now have different loginservers
      • Telia changed the behavior of their loginservers, causing autodetection to give false hits

    v5.06 - 2004-05-11
      • The beta expiration check was not entirely disabled from the beta test period, it is now completely disabled

    v5.05 - 2004-05-09
      New Features:
      • Added support for Tele 2
      • Added support for ComHem IC8000
      • Added a stop button for the relogin timer
      • Added email-verify field in registration dialog
      • HTTPS / SSL, Secure HTTP now handles expired certificates on the loginserver
      • Updated the registration process and texts
      • Removed expiration date (2004-12-31)
      • NIC Autodetect log-loop when an interface was not active removed
      • Fixed error handling to always report an error when something goes wrong at login

    v5.02 - 2004-01-21
      New Features:
      • The license key verification now allows keys for all 5.x versions

    v5.01 - 2004-01-11
      New Features:
      • Configuration option to enable/disable log file (was on by default before)
      Bug fixes:
      • LFCK would not start as a service if an earlier version had another binary path and was not correctly uninstalled

    v5.0 - 2004-01-08
      This is the first release of the totally rewritten LFCK with plenty of great new features!


    Feel free to contact me at support@lfdomain.com if you have any questions or suggestions regarding LF Connection Keeper

    Please respect that I do not leave any support regarding your internet connection or LAN.
    Your ISP's support beares that responsibility.

    Join our mailing list to receive information about program updates in your email

    Price List

    LF Connection Keeper is shareware for commercial and educational use. It's freeware for private non-commercial use only.

    If you're running a business from your home you'll need a commercial license.

    In order to run LF Connection Keeper on a server you'll need one server license per server and additional client licenses for every client computer that advantage of the servers Internet connection.

    To buy licenses or if you have any order related questions, contact me at order@lfdomain.com.

    License Type Server Client
    Commercial 400:- 200:-
    Educational 300:- 150:-
    Private (optional) 100:- 100:-
    Prices are in Swedish Krona

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