I had this error when I was working on my Oracle database, and though of sharing the solution with you:
The error is:
ORA-24324: service handle not initialized
ORA-01041: internal error. hostdef extension doesn’t exist
This error means that Oracle database is not able to start, or it is not able to start it’s background processes. So to fix this go and check your services for the database if they are running.
After that start your oracle listener if it is not running yet via “lsnrctl start” as below:
Now start your SAP services. To make sure that your SAP application is running, and connected to the database run “R3trans -D” as below. The return code should be 0 for success:
Hope this was helpful.