Tutorial: Troubleshooting dial-up connections

Though considered a dying breed by most, dial-up connections are still used by many users staying in hotels without high-speed access, or in geographical regions to which broadband connectivity does not reach.

There are a few significant troubleshooting issue associated with dial-up connections with some straightforward solutions.

Dropped, slow, or non-existent connections Dial-up connections are inherently more flaky than cable, DSL and other methods under most circumstances. Tracing the direct cause of the slowness or lapsed connectivity can be difficult, but there are a few general workarounds you can use in order to help encourage a smooth connection.

Check settings If you have a connection that drops at a regular interval, make sure that the "disconnect if idle" setting is turned off in System Preferences via the following steps:

1. Open the Network pane of System Preferences.
2. From the Show: menu, select Internal Modem
3. Select PPP, then PPP Options
4. Modify the "Disconnect if idle for..." setting or turn it off

Change modem definition In the "Show:" menu of "Network" pane, select "Internal Modem." Click on the "Modem" tab, and then select "Apple Internal Modem (v.34)" rather than "Apple Internal Modem (v.92)." Some users have found that using the alternate modem definition allows more consistent connectivity.

Disable Norton Firewall A few readers have reported that disabling Norton's Personal Firewall (part of Symantec's Norton Internet Security package) allows problem-free dial-ups.

Cocktail dial-up optimization Some readers have reported using the shareware utility Cocktail's dial-up optimization option (found in Network -> Optimization -> Dialup from the application's main interface window) helps to eliminate some of the aforementioned problems.

Use an alternate USB modem For some Internet service providers, Apple's internal modem configuration may be the problem. In addition, the external USB modem offered for current Macs has been known to cause kernel panics on occasion. As such, use of a third-party external USB-based modem is a suitable option for some users.

Re-install Mac OS X Though drastic, a full re-installation of Mac OS X from the original optical disc has proved successful in eliminating dial-up issues for a handful of readers.

Disable all other ports Try creating a new network location (in the "Network" pane of System Preferences), then scroll down to "Network Port Configurations" in the "Show:" menu. Uncheck all network ports except for the dial-up device ("Internal Modem" in most cases).

Remove phones from same line Try systematically removing any phones from the same line on which you are attempting to dial-up, as some users report possible interference.

Change IPv6 settings In the "Show:" menu of "Network" pane, select "Internal Modem." Click on the "TCP/IP" tab and then click "Configure IPv6." Choose "Off" in the resulting pull-down menu.

Check for electrical disturbance Try this test: Pick up a phone on the same line as your dial-up connection and dial a single number (this will get rid of the dial tone). Then touch your Mac with your hand. Do you get a buzzing sound in the phone earpiece? Now connect a grounding wire to your Mac. Does the buzzing sound go away? If so, then the electrical disturbance may be causing your disconnect problem.

Sleep/shutdown issues In some cases, dial-up connections can prevent proper sleep and shutdown routines. If you are experiencing such issues and have an active dial-up connection, try disconnecting before putting your Mac to sleep or powering it off.

Eliminate hanging disconnect 

If you find that your Internet Connect status (either in the Internet Connect application or the modem status indicator in the menu-bar) displays a "Connecting" status then a constant "Disconnecting" status, try putting your system to sleep for a few seconds and then waking it back up. This should stop the "Disconnect" process.

Another method for dealing with the hanging disconnect is to use the script available at http://www.shopperturnpike.com/usefulsoftware/endhangingdisconnect.html.

This script repeats the killall command  on a process vital to dial-up connectivity 5 times (with a 5 second delay in between tries).

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