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Internet Access with System 6


This document describes how to get online with a Macintosh running System 6 via a dial up modem connection to an ISP (Internet Service Provider). Advanced users can vary these procedures to connect to the internet via a shared connection on another Mac or PC or via a LAN with internet access.

There are lots of documents that explain how to setup internet access for a classic Mac running System 7.x. For System 6, things are easier because the number of options and applications is so much smaller. However, the system software (MacPPP and MacTCP) that you need to run is trickier to configure than more recent versions. This document is long because it contains a lot of detail, not because the procedure is impossibly difficult.

Suitable Macs

I'm going to focus on computers from the "Mac II class" with a 68020 or 68030 processor designed to run System 6: Mac II with or without floppy drive upgrade, Mac IIx, SE/30, Mac IIcx, Mac IIci, Mac IIfx, Mac IIsi, Mac LC. These models are faster than the compact systems and support bigger monitors and graphics cards. 8Mb of RAM is useful so that you can run the Multifinder; more than 8Mb is overkill unless you have a third party memory manager that will let you access it with System 6. A hard disk is strongly recommended -- all of the Mac II class machines support an internal SCSI disk that you should be able to buy second hand for next to nothing.

Note that this page is entitled "Internet access" -- for mail, usenet news, telnet applications -- and full "web access" is not possible. There is no graphical web browser for System 6 and the only browser that works is limited to the HTTP 1.1 standard so the small number of pages that load can look very strange. Assuming that you have a shell account on a Unix or similar system, an alternative is to use the Lynx text based browser from a telnet terminal. I'm not aware of any chat or instant messenger clients for System 6.

Internet access from a 68000 Mac is even more limited. The Mac 128K, Mac 512K and 512Ke models don't have enough RAM to run MacTCP; I'm working on other ways to get a 512K on the internet (see networking index). Other 68000 Macs (Plus, SE, Classic, Portable, PowerBook 100 and Lisa 2/MacXL) with 1MB RAM or more are able to run MacTCP although some people report problems with MacPPP.

Support from your ISP

Don't expect much sympathy or assistance from your ISP if you have problems connecting to them using such an "ancient" setup. I strongly recommend making sure that you can connect to your ISP from a modern "supported" system before you try to set up your older Mac. Make sure that the dial up details supplied by your ISP (phone number and password, for example) are right by testing them first.

The absolute minimum information you need is your dial up connection telephone number, your authentication details (username and password) and your ISP's DNS server IP addresses. If your ISP has given you a static IP address, you'll need to know that address and your ISP's gateway IP address. Don't forget that you'll need your ISP's server addresses for mail and usenet news if you're going to benefit from your new connection.

Software Requirements

System 6 -- 6.0.8 or possibly 6.0.7 (older versions may have problems with MacTCP). I'm assuming that System 6 is already installed and configured on your Mac. If you need to install System 6 from scratch, try some of the System 6 links at the bottom of this page.

MacPPP 2.0.1 -- in my experience this is the one to use with System 6. Your mileage may vary with later or earlier versions.

MacTCP 2.0.6 -- For many years, MacTCP was an expensive extra to the Macintosh system software and it is not supplied with System 6. It is now freely available and you can now get a copy from the System 7.5 software distribution, from Apple's MacTCP Software Developers' Kit or from a good number of unofficial web resources.

MacTCP 2.1 is the latest unofficial update from a New Zealand developer, Glenn Anderson. MacTCP 2.1 may be required for some ISPs (see the University of Oregon description of this problem). You will need a clean, unused copy of the MacTCP 2.0.6 control panel that you can patch to version 2.1. MacTCP 2.1 has a simpler revised user interface.

Modems and Cables

There is no need for the fastest V90/56Kbps modem for basic internet access unless you will be transferring large files by FTP or as mail attachments. Older Macs use an external modem which plugs into the corresponding modem port on the computer. Global Village and others produced modems that plug into the Mac ADB (mouse/keyboard) port -- you should check suitability with your Mac and System 6.

If you are on a budget, a second hand 14.4Kbps or similar modem (less than £10) is adequate. Check with your ISP and find out the minimum standard/speed for modems that they support. Make sure that documentation for your modem is available on paper or online so that you can set the external switches correctly.

You will probably need an init (initialisation) string to set up your modem. Modern Macs and PC use prepackaged modem scripts that tell the modem what type of flow control to use or what to do if somebody tries to dial into your computer. Older systems use an init string -- an incomprehensible set of Hayes AT commands &endash; to do the same job. Your modem manual may list a suitable string or try the modem help pages.

A "hardware handshaking" (RTS with DTR flow control) modem cable is recommended for faster, more reliable connections. Most "standard" Mac modem cables do not support hardware handshaking so purchase with care. If you wish to make your own, here are the pinouts that I use:

Apple Mini-Din 8

Modem D25 Male


1 HshkOut

4, 20


2 HshkIn



3 TxD-



4 Ground



5 RxD-



6 TxD+

not connected at modem




8 RxD+

7 at modem or 4 at Apple


The DTR connection (pin 20 at modem) is optional. It allows the modem to be used in non-handshaking mode. If pin 20 (DTR) is enabled, the modem init string should include &D0.

Installing MacTCP and MacPPP

If you have previously tried to install MacTCP or MacPPP, it is important to remove any old components before you install the new ones. Open your system folder and scroll down the list of files. Drag any files called PPP, Config PPP, PPP Preferences, MacTCP, MacTCP DNR or MacTCP Prep out of the system folder completely. Store the old files in a To Junk folder, just in case you need to restore them later. Don't trash them until you are abolutely convinced that MacPPP/MacTCP is installed to your satisfaction.

Locate your decompressed copy of the MacPPP package. This should contain:

  1. Place the PPP system init and Config PPP control panel in the system folder.
  2. Locate your copy of the MacTCP control panel. Place it in the system folder.
  3. Restart the Macintosh before starting to configure the two control panels.

Configuring MacPPP

From the Apple menu, select Control Panel. Scroll down the list of control panels and select Config PPP. The default settings are displayed below.

Unless you have plugged your modem into a different port, you don't need to change any settings on this page. Click on the Config button to display the dialog below. This example shows how to connect to an existing on Freeserve, a free ISP in the UK.

You need to provide the details below.

PPP Server Name: A useful name for this PPP configuration. You can have different configurations for more than one ISP.

Port Speed: The port speed should be set to a higher speed than the modem speed because data is compressed over the telephone line and decompressed by your modem. A Mac II or better will usually work happily with a port speed of 57600 bps with a 14400 bps or faster modem. Reduce the speed if you have connection problems. For a 68000 Mac, you may need to set the port speed as low as 19200 bps.

Flow Control: If you are using a hardware handshaking cable, select CTS & RTS (DTR). For a "standard" cable select Normal.

Tone Dial or Pulse Dial: Modern phone systems use tone dialling. If you don't know about your system, ask your phone system provider.

Phone num: Provided by your ISP.

Modem Init: See your modem documentation. My modem is preset to the correct configuration so no init string is required.

Connect Script: Most ISPs do not require a connect script. You will have been supplied with this information if it is required.

LCP Options: Not required unless stated by your ISP.

IPCP Options: Not required unless stated by your ISP.

Click on the Authentication button to display the dialog below.

Enter the Authentication ID (user name) and Password provided by your ISP. The other settings can be left as their default.

Click OK to close the authentication dialog. Then click on the Done button in the configuration dialog to complete the PPP configuration.

Configuring MacTCP

From the Apple menu, select Control Panel. Scroll down the list of control panels and select MacTCP. Typical settings are displayed below. Select the icon labelled PPP and click on the More button.

The MacTCP configuration interface is quirky, to say the least. You may need a couple of attempts to get all the settings right.

Obtain Address panel: Select Server if your ISP allocates a different IP address each time that you connect to them &endash; this is the most common option. Select Manually if you have a static IP address allocated by your ISP.

IP Address panel: Select Class C from the pull down menu. If necessary, move the peculiar slider to the right so that Subnet Mask reads

Domain Name Server Information (DNS) panel: Your ISP should supply you with IP addresses for one or more of their DNS servers. For each DNS server address, type a . (period or full stop character) in the Domain field and type the address in the IP Address field.

Routing Information: Ignore this if your ISP allocates a different IP address each time that you connect to them &endash; this is the most common option. If you have a static IP address allocated by your ISP, type in the Gateway Address supplied by them.

Click OK to save these settings. Note that the IP address field in the MacTCP opening window will read

Close the main Control Panel window and restart the Macintosh.

Connecting via MacPPP

Open the Control Panel from the Apple menu. Select Config PPP and click on the Open button. A progress window will display the status of your PPP connection and any errors will be reported.

A successful PPP connection typically takes about 20 seconds to complete and not a lot will appear to have happened. If you look closely at the Config PPP panel, you should see the message PPP Up with two smiling faces. You can now test out your connection by running one of the range of System 6 internet applications.

Internet Software

I've used this software successfully with System 6:

Other people have reported using this software successfully with System 6:

 Jag's House has a fuller list of internet applications for older Macs.

Trouble Shooting

The most common causes of PPP problems are incorrect flow control settings (or wrong modem cable) and bad init strings. Trial and error tends to be the only solution. The release notes for MacPPP contain some useful tips.

Resetting PPP

Remove the PPP Preferences file from your system folder to clear all of your dialup settings. Don't delete the file unless you are really sure...

Resetting MacTCP

If reinstalling or reconfiguring MacTCP, delete the files MacTCP Prep and MacTCP DNR from your system folder.

Useful Links

Jag on system 6 Internet apps --

System 6 Heaven pages --

Old macs on the Internet -- mainly System 7 --

Modem support including init strings --

Global Village modems --

US System 6 source -- -- versions for other countries are also available.

MacTCP software developers' kit from Apple --

MacPPP download with MacTCP --

Eudora Lite 1.3.1 --

University of Oregon on the MacTCP problem --

MacTCP 2.1 patch --

Copyright information: If you wish to use any images on these pages, please contact the author, Phil Beesley on