In some conditions, a problem with a phone line or with PC can cause an internal dial-up modem to become insensitive. Usually, this can be solved by rebooting PC. Though, more serious problems may require to be addressed by interfacing with hardware directly. If this occurs, reset internal modem through Windows Device Manager or by using a third-party terminal program.

Instructions

Using the Device Manager

1. Step 1

Push Windows logo and R keys on keyboard concurrently, and type devmgmt.msc in window that shows. This appears Windows Device Manager.

2. Step 2

Click on plus symbol beside "Modems."

3. Step 3

Right click on modem, and tick "Disable."

4. Step 4

Right click on modem once more, and click "Enable." This procedure turns the interior modem off and on; at hardware level which solves many problems that restarting is unable to repair. If it does not, keep Device Manager open and go to next sector.
Using a Terminal Program

5. Step 1

Right tick on modem in Device Manager, and tick "Properties." Pick "Modem" tab, and create a note of number next to word "Port," e.g., "COM3."

6. Step 2

Download and install PuTTY. Run the program.

7. Step 3

Click radio button beside "Serial," and enter port that you searched into box next to "Serial line." press "OK." This shows a black terminal window.

8. Step 4

Type "ATZ" and push Enter. This is a worldwide command that tells virtually all modems to reset. The modem must react, "OK." If it does not, there may be a hardware problem that needs extra troubleshooting. Call modem or PC Company about a possible hardware substitute.