Fax transmission may not finish after a connection is established in Windows Vista

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256986 Description of the Microsoft Windows registry
When you try to use Windows Fax and Scan to send or receive a fax in Windows Vista, the transmission may not finish after a connection is established.
This issue may occur if one of the following conditions is true:
  • There is line noise over the telephone line that is connected to the modem.
  • You experience unexpected behavior from the modem.
  • There is a timing issuebetween the computer and the modem.
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To work around this issue, you must use a different class support to retransmit the fax. To do this, follow these steps:
  1. Click StartStart button, type device manager in the Start Search box, and then click Device Manager in the Programs list.
  2. Expand Modems, right-click the modem that you use, and then click Properties.
  3. On the Diagnostics tab, click Query Modem.
  4. In the Command column, locate AT+FCLASS=?, and then note the value in the Response column.

    Note If the Response column contains a value of 1, 2, or 2.0, the modem supports Class 1, Class 2, and Class 2.0, respectively.
  5. Click StartStart button, type regedit in the Start Search box, and then click regedit in the Program list.
  6. Locate and then click the following registry subkey:
  7. Expand TAPIDevices, and then click the device ID of the modem.
  8. Click Modem, right-click FixModemClass, and then click Modify.
  9. In the Value data box, type one of the following, depending on the class that you want to set:
    • Type 1 to set the fax modem to use Class 1
    • Type 2 to set the fax modem to use Class 2
    • Type 20 to set the fax modem to use Class 2.0
  10. Exit Registry editor.
  11. Restart the fax service. To do this, click StartStart button, type Services in the Start Search box, and then click Services in the Programs list.
    User Account Control permission If you are prompted for an administrator password or for a confirmation, type the password or click Continue.
  12. In the Services list, click Fax, and then click Restart.
  13. Try to send the fax.If the issue occurs again, repeat steps 1 through 12 and set the modem to use a different class.
More information
For more information about sending a fax in Windows Vista, visit the following Microsoft Web site:
Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use for other considerations.

Article ID: 927526 - Last Review: 01/16/2015 09:20:30 - Revision: 1.0

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