When you try to start Control Panel / Modems or Control Panel / Telephony.. / Unimodem.. / Configure,
the hourglass flashes briefly but the dialogue box does not open.
If you try to open modem properties from a CMD prompt, it doesn't open:
control modem.cpl
rundll32.exe shell32.dll,Control_RunDLL modem.cpl
NOTE: The rundll32.exe commands are case sensitive.
Possible causes of this difficulty are:
1. Modem.cpl is missing or damaged. Expand it from the CD-ROM:
expand <CD-ROM:>\i386\modem.cp_ %SystemRoot%\System32\Modem.cpl
2. The %SystemRoot%\System32\Modem.cpl file doesn't have proper permission. Set the following permissions:
Administrator - Full Control
Everyone - Read
Server Operators - Change
SYSTEM - Full Control
3. A registry key/value is missing or damaged. Use Regedt32 to verify / fix:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Class\\{4D36E96D-E325-11CE-BFC1-08002BE10318\}
Value Name: Installer32 Data Type: REG_SZ String: Modem.Cpl,ClassInstall32 Value Name: Icon Data Type: REG_SZ String: 0 Value Name: Default Service Data Type: REG_SZ String: Modem Value Name: Class Data Type: REG_SZ String: Modem Value Name: <No Name> Data Type: REG_SZ String: Modem
