Oracle cannot start the listener

Problem description: 1. the remote connection is normal. You can use pl/SQL developer to link to a remote database, but the local database service cannot be linked after it is enabled. if the local Database Listener cannot be opened, enter lsnrctl start; sqlplus/nologconn sys/[database username] I @ orcl as sysdba; start at the command prompt to open the local database, however, pl/SQL developer cannot be linked to the local database, prompting that there is no listener. When a local listener is started in windows Service, the oracleoradb10g_home1TNslistener service on the local computer fails to be started, this indicates the exception where the local listener has been occupied: 1. when you enable the windows service, there are several listeners in it. These listeners are not started in the service. 2. open the registry and find HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/services/CMDL ******* lister. Several Different listeners are found. solution: 1. check the online information. In this case, the configuration file information is incorrect. The Listener cannot correctly read the configuration information of the local machine. 2. view the local configuration file my oracle is installed in E: \ oracle \ product \ 10.2.0, view the configuration file E in the installation path: listener under \ oracle \ product \ 10.2.0 \ db_1 \ network \ ADMIN. ora and tnsnames. ora configuration information, and view the host options under it, are correctly directed to the local machine, its name is localhost, or the computer name of the Local Machine, query no fault, but still cannot link the specific solution: 1. use the netConfiguration assistant tool that comes with oracle to delete all the listeners on the local computer, and then create a new listener named listener. The listener points to the local database. 2. view the local windows Service, start the newly created listener, and try to start it. If the newly created listener cannot be started, enter the registry, find HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/services/CMDL ******* lister, delete all other unwanted listeners except the newly created listener, and restart the computer. enable the local database service, enable local listening, and log on to the database. cause Analysis of problem solving: the cause of this problem is that multiple local listeners are enabled, so that when the local listener is enabled, the system prompts that the listener is running and forces the current listener to end. after the analysis, we found that the remote database was previously used and we accidentally set up more listeners. When we linked the remote database, we only needed to set up different services, only one listener needs to be created. now I have posted a lot of posts on the Internet to solve this problem. To sum up, there are the following. view the database configuration file listener. ora and tnsnames. the host value in ora points to the local machine correctly. 2. Check whether the imagePath under the HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/services/CMDL ****** lister has a value. If no value is added, it points to your oracle database, for example, if my local value is E: \ oracle \ product \ 10.2.0 \ db_1 \ BIN \ TNSLSNR3. check whether the database environment variables are configured, I feel that this is no big deal. Then wineer200, author of the solution I mentioned.