问题
I am a big beginner using Oracle Database 11g Express and tried it for the first time today. I only got theorical knowledge on databases (learned SQL but never used it). So, I installed Oracle 11g today (gave them the password for system when needed). I then proceeded to launch 'Start Database' followed by the SQL command line. I entered connect SYSTEM/password but received :
ERROR:
ORA-12638 : Credential retrieval failed
Following advices of various forums, I changed my sqlnet.ora file, replacing SQLNET.AUTHENTICATION_SERVICES = (NTS) by SQLNET.AUTHENTICATION_SERVICES = (NONE)
Didn't change anything else. But now I get the following errors :
ERROR:
ORA-01034: ORACLE not available
ORA-27101: shared memory realm does not exist Process ID: 0
Session ID: 0 Serial number: 0
I did nothing else besides installing this software and launching Start Database.
Can't really find an in-depth tutorial for it by the way.
EDIT : I followed @vercelli 's comment and this topic. Seems like you can't install Oracle 11g XE with an user account connected to the entreprise domain (installation process can't connect to the database). So, I followed these advices : I uninstalled Oracle XE, logged as a local user, installed Oracle XE there and it worked :
.
But when I logged back as an user domain, I had the same issues as before : ERROR: ORA-12638
EDIT : Works as a domain user after changing the sqlnet.ora file as attempted before. (see my answer) Might not be optimal.
回答1:
I followed @vercelli 's comment and this topic. Seems like you can't install Oracle 11g XE with an user account connected to the entreprise domain (installation process can't connect to the database). So, I followed these advices : I uninstalled Oracle XE, logged as a local user with administrator privileges , installed Oracle XE there and it worked on the local user:
.
But when I logged back as an user domain, I had the same issues as before : ERROR: ORA-12638
So, I changed my sqlnet.ora file on the domain user as I had tried before (after advices from different forums who had this ORA error) :
SQLNET.AUTHENTICATION_SERVICES = (NTS)
to
SQLNET.AUTHENTICATION_SERVICES = (NONE)
And now It seems to work as a domain user too : I was able to connect.
来源：https://stackoverflow.com/questions/38463516/error-ora-12638-in-oracle-database-11g