You should always use the latest version of the network components available for your version of 4D.
4D Client/Server is among the most reliable Client/Server database solutions available. Nevertheless, it is reliant on various other system components to work, and there are many problems that can prevent a reliable connection between the client and the server from being made.
-10001 and -10002 errors on the client usually indicate a problem with creating or maintaining a network connection between the client and the server. One common cause of this problem is that the server application crashes, which can occur for a variety of reasons. In this case, you need to find out what causes the crash and fix it.
If the server is still running and you are getting the error, we can distinguish two cases: either you are never able to get a connection, or you get this error a while after you start using the Client/Server system.
In the case that you are never able to connect, you should first check that the client and the server both have the appropriate network protocol working:
Chances are that you have given your structure file a long name. Mac OS files can have names of up to 31 characters. When you first connect to a 4D Server, 4D Client tries to create two files in your Preferences folder, and names them DB_name.res and DB_name.rex, where DB_name is the name of your structure file. If the name of your structure X has more than 27 characters, 4D Client will not be able to create these files, and you will get an error message. Shorten the name of your structure in the Finder.
Also, the client machine may not have enough disk space to create the cache files. Check the amount of disk space available. If this still does not solve the problem, remove the database folder that was created in the 4D folder on the client.
Finally, if you are connecting to a Macintosh server from a Windows client, you may have an invisible icon file in your Win4DX folder. The simplest way to remove this file is to save any normal document called icon into this folder on the server, and to click on the OKbutton when asked if you wish to replace this file. Then you can trash your new icon file normally.
4D Version 6.5 network components use a new default port number. Previous to version 6.5, the TCP and ipx network components default ports were 14566 and 1234 respectively. Version 6.5 of the network components uses port 19813 for both TCP and ipx protocols. The new port number is used so that there is less chance to see old network components that are not compatible. Version 6.5 network components are not compatible with version 1.5.x of 4D.
The new port number will create a problem for those running version 6.0.x and 6.5 databases simultaneously with different port numbers. Broadcasts and connections to 6.0.x databases using port 14566 cannot be made while using the 6.5 network components on port 19813. To fix the problem all that needs to be done is to change the port number back to 14566 after you install the new 6.5 network components. Once the port number is changed broadcasts and connections can be made with both 6.5 and 6.0.x databases using the 6.5 network components.
Technical Note 96-56 "Launching Multiple Instances of 4D Server..." (PDF format) has a detailed description of how to change the port number using 4D customiser 6.0.x.
Chapter 8 of the 4D customiser documentation describes the different options
for port numbers and broadcasting.
Important: As in the past, 4D recommends using the same version of network
components for both the 4D Server and 4D Client applications.