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JSI Tip 2261. Windows NT 4.0 only attemps to redial a lost connection 15 times?

If you have configured DUN to redial your ISP, you may receive the following after 15 attempts:

Could not detect modem. It may be in use, turned off, or not installed properly.

If your modem is based upon the Rockwell chip set or USR/3Com set, it may have blacklisting enabled. The ITU standard dictates that the modem blacklist the phone number after 15 failed attemps.

If this happens, you must wait for the modems internal time-out or you must reboot.

You can turn off blacklisting by modifing the modem initialization string:

    Command  Modem type
    %TCB     Rockwell based
    S40=2    U.S. Robotics/3Com
    S40=7    U.S. Robotics/3Com
You may want to contact your manufacturer for an updated .inf file.
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