Error Codes and Solutions
-7117 3, 10, or "unexpected" [File] Missing No dial tone
stuck on "determining protocol" Error of type -119 Netscape has quit Error Type 11 ERROR CODE LIST

Error -7117 or hangs showing status as "Determining Protocol"
If you get this specific error, they are probably using Apple Remote Access. Click on the Options button in the lower part of the Remote Access screen. Next, select the Protocol tab. If they're receiving this error, the selection "Use protocol" is most likely set to Automatic. Click on the down arrow next to Automatic and choose PPP. Click OK. The new settings are immediately in effect. They will be asked to save the changes when the Remote Access control panel is closed.

"No dial tone" error message
Go into the Modem control panel and check "Ignore Dial Tone" (sometimes a poor line or a line with voice mail will provide a dial tone that the computer can't recognize). If after you do that they get a "modem not responding properly" error, go into Remote Access and put some commas in front of the phone number.

Either "Netscape has unexpectedly quit, because an update to this file is required..." or "Error of type -119"
Remove the Talkback folder from the Netscape folder (located in the hard drive).

Error Type 11
This is a general hardware expception error. Because it is general, it doesn't say what the problem is or even where it is. They definitely need to talk to Apple or a repair person.

Error 3, 10, or '[Application] could not launch because an unexpected error has occured'
This might be caused by the Internet Config extension having been removed. The problem affects OS 8.1 to 9.0.4, but the solution provided by Apple only works for those systems with 9.0 or later. Specifically:

If your computer has Mac OS 9.0 or later, use the Software Update control panel to install URLAccess 2.2.1 or later. Make sure that the Internet Config Extension is installed in the Extensions folder inside the System Folder. Note: The Internet Config Extension does not appear in the Extensions Manager control panel. Check inside the Extensions folder itself for the presence or absence of the Internet Config Extension