Unable to create socket on port 21

THE INFORMATION IN THIS ARTICLE APPLIES TO:

• EFT Server (all versions)

SYMPTOM

Unable to create socket on port 21

RESOLUTION

The error is generally the result of running the Microsoft IIS FTP server and the EFT Server/Secure FTP Server residing on the same computer and both trying to use port 21.

(This error can also occur if you have more than one Site trying to use the same IP address:port combination. Refer to KB Article # 10066 - ERRMSG: IP address or Port conflict, Cannot start Site for more information.)

By default, the FTP server in Microsoft IIS binds to port 21 on any and all IP addresses. If you are running both the IIS FTP server and EFT Server/Secure FTP on the same computer, you will need to disable socket pooling for the IIS FTP server (or use a different port for EFT Server/Secure FTP Server/CuteFTP for FTP).

To disable socket pooling in IIS FTP server

1. In Microsoft Internet Information Services, stop the FTP site (see below).

2. Open a command prompt.

3. Change directories to C:\InetPub\Adminscripts.

4. Type the following command and then press ENTER:

   CSCRIPT ADSUTIL.VBS SET MSFTPSVC/DisableSocketPooling TRUE

   You should get a response like this: disablesocketpooling : (BOOLEAN) True

5. Exit the command prompt and restart the FTP site. This should prevent IIS from binding to all IP addresses on port 21, freeing up an IP address for EFT Server/SecureFTP Server/CuteFTP on the default FTP port of 21.

More information on Microsoft IIS socket pooling, refer to the following Microsoft Help and Support pages:

• IIS Binds To All Available IP Addresses When It Starts
• How to Disable Socket Pooling