Problems Connecting at High Speeds with US Robotics 56K WinModem

Problems Connecting at High Speeds with US Robotics 56K WinModem

This applies to:

• Microsoft Windows Millennium Edition
• Microsoft Windows 98

When you try and connect to your Internet Service Provider (ISP) using a US Robotics 56K WinModem, an “LT Winmodem” or an “HSP Winmodem” you may experience the following problems when trying to connect at speeds above 33.6 kilobits per second (Kbps):

• The modem may randomly disconnect from your ISP.
• When you download files, the connection speed may decrease and not resume to its original speed during the session.

This is usually caused by either line noise or a resource conflict between the WinModem and another device in your computer.

To work around this problem try this:

If you suspect Line Noise:

If line noise is preventing consistent connections to your ISP, follow these steps:

1. Click Start, point to Settings, and then click Control Panel.
2. Double-click Modems.
3. On the General tab, click your modem, and then click Properties.
4. On the Connection tab, click Advanced.
5. In the Extra Settings box, type one of the following modem initialization strings: s32=66 s32=34 
6. Click OK, click OK again, and then click Close.
7. Test to see if the behavior is resolved. If the behavior is not resolved, repeat steps 1-6, using the other modem initialization string in step 5.

The “s32=66” initialization string disables support for the V.90 standard, and the “s32=34” initialization string disables support for the X2 standard. The following explains the V.90 56K modem standard. When you use a V.90 modem, you may be unable to establish a V.90 connection if there are problems with the phone line, modem, or your Internet service provider (ISP).

A V.90 connection relies upon the modem, the telephone line, and an ISP.

The modem must support the V.90 standard, but its maximum default transmission speed can vary. For example, the Federal Communications Commission (FCC) requires that no telephone device may exceed a certain power level during a transmission. Some modems support the V.90 standard, but use a 53.3K transmission speed to conform to the FCC rule.

To determine if your modem supports the V.90 standard, follow these steps:

1. Click Start, point to Settings, click Control Panel, and then double- click Modem.
2. On the Diagnostics tab, click the modem, and then click More Info.
3. Locate the line that begins with “ATI7.” If your modem supports the V.90 standard, “V.90” should be listed beside this option.
4. Click OK.

The reliability of the connection depends upon the quality of the connection from the phone line to the local telephone switch, the ISP’s connection to its telephone switch, and a telephone route that can connect the two switches together (some ISPs use a local number for you to connect to and then the call is forwarded). These connections must support the V.90 standard and be able to sustain the transmission speed.

Because the telephone route connection can change depending on the phone traffic, try connecting to your ISP during different times of the day over a period of time. Also, you can contact your telephone company and inquire if the phone lines used support V.90 connections.

The ISP must have telephone lines and modem servers that support V.90 connection speeds. It is possible that although the ISP’s modem server supports V.90 connections, some of the connecting phone lines may not. Also, the telephone number that you use to connect to your ISP may not support V.90 connections. In this case, you may need to contact your ISP to determine which of their telephone numbers support V.90 connections in your area.

If you suspect a Resource Conflict:

You may want to review the following troubleshooting procedures in the Microsoft Knowledge Base:

Q190554 Troubleshooting Modem Problems in Windows 98