Oracle 18 on Windows with long hostnames doesn't talk to the local listener?

Note: Initially this was about *installing* Oracle 18c XE on a Windows machine with a long (> 15 chars) hostname. During our further tests we then noticed that **Oracle 18c XE does not work properly at all on a Windows7 or Windows 10 machine with a host name longer than 15 characters.** # Listener Problem When we switch a correctly *working* VM machine that has Oracle 18x XE installed from a short hostname/computername (e.g. MYHOST) to a **long (> 15) name** (e.g. MYVERLONGHOSTNAMEXYZ) the **listener stops being able to hand off the connection to the OracleServiceXE instance**. Specifically, the error we get is: ORA-12518: TNS: Listener konnte Client-Verbindung nicht weitergeben ORA-12518: TNS: Listener could not hand off client connection * This error occurs with both sqlplus SYSTEM/***@XE and sqlplus SYSTEM/***@XEPDB1 - bith entries are set up in tnsnames.ora and tnsping can see them. * The Oracle XE instance is up and running. * It **is** possible to connect via sqlplus SYSTEM/***(without @SID) * listener.ora, tnsnames.ora do *not* contain any hostnames, they only contain the (local) ip address. ## TL;DR Question Is anybody able to switch an Oracle Test machine with Oracle 18c (/ XE) running to a long Windows hostname (so that the hostame is then longer than the NetBIOS name) and still connect to the instance via the local listener? ------- ------- *Initial installer problem description:* We're having troubles getting Oracle 18c DBCA (XE or non-XE) working on Windows machines (both Win7 and Win10) where the machine name is longer than 15 characters (the NetBIOS limit). It **seems** the Oracle 18 dbCA tool refuses to pass some checks when the machine name is > 15 characters. (see: https://community.oracle.com/message/15361496#15361496) Now, without going into further details, I am currently investigating: * Does Oracle database 18 docs say anything about the maximum length for the computername on Windows installation? * Can someone provide a counterexample where Oracle 18c (preferrably: XE) has been successfully installed on a windows machine where the computer name is > 15 chars? ---- Note: This error halts the dbCA, effectively stopping the Oracle 18c (XE) setup from doing it's job: 18c XE setup will only install the binaries and the listener, no instance will be created and no instance can be created via dbCA afterwards. The same is true for the full 18c installer, although that one is more flexible in it's invocation options and one might get it to work somehow.