Windows 10 VPN error: The modem (or other connecting device) is already in use...

[Hectorj3]

Hi

I am receiving the error message "The modem (or other connecting device) is already in use or not properly configured" when I try to use VPN to an MX64W with Windows 10. The Windows event viewer indicates an error 633

Does anyone know what may be happening?

Saludos

Carpe diem

[BrechtSchamp · Accepted solution]

I assume you already tried restarting your computer. Have you tried this:

Use the netstat command to find the program that uses port 1723. Then, end the process for that program. To do this, follow these steps:

1. Click Start, click Run, type cmd.exe in the Open box, and then click OK.
2. At the command prompt, type the following command, and then press ENTER:
   netstat -aon
3. In the output that is displayed, identify the process ID for the program, if any, that uses TCP port 1723.
4. At the command prompt, type the following command, and then press ENTER:
   taskkill /PID PID /F
   Note The taskkill command ends the process that corresponds to the process ID number. The /F option is used to forcefully end the process.
5. At the command prompt, type exit, and then press ENTER to quit the command prompt.

That might tell you which program/service is causing issues.

source: https://support.microsoft.com/en-us/help/885959/error-633-the-modem-or-other-connecting-device-is-al...

[Hectorj3]

Thanks for your help.

Although netstat did not report that port 1723 was in use, I modified the Windows registry as indicated and the problem was solved.

Saludos

Carpe diem