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Why can't the client connect to the server or is the line offline?


The XPhone Client reports at startup that no connection to the XPhone Server is possible or the line is offline.

Cause 1:

The system time between the client machine and the server machine does not match

Uhrzeitdifferenz Server Client

If the time does not match, the following error may occur:


Cause 2:

Check the following registry entry on the affected client machine:


Here the following values should be stored in the key "Functions":










Add the missing values and restart the computer. Afterwards you can log in again.

Cause 3:

Check whether the firewall you are using is blocking port 2230. To test this you can use the PortTester provided by us or, if the Windows feature Telnet-Client is installed, check the connection via Telnet.

For example, using the command line call: "telnet <server IP or address> <port>"

Cause 4:

The Connect Client may already be unable to connect to the local UCSingleSignOn via named pipes. As a result, it does not receive login credentials and cannot log in to the server.

The two test programs host.exe and guest.exe can be used to check whether Named Pipes work properly on the client computer. This must work without admin rights! If this is not the case, it is a XPhone-external problem and the administrator of the system must look for the cause elsewhere.


For the test, proceed exactly according to the instructions in the ReadMe.

Related article:

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