MSDAORA,IIS,ORA-12154: TNS:could not resolve service name

Question

Hi All,
I have a Web Service that coded in VS2008, using ORACLE DB(9i).
At a time the application working fine and I can access and do everything with database.
Some other time database server is down for scheduled maintenance. If I try to run the application at this point of time it will raise err "ORA-12154: TNS:could not resolve service name".
When i reset iis it start to work fine for a while.Then same problem occurs again.
My connection string is connectionString="provider=MSDAORA.1;data source=***;user id=***;password=***;"
is there any solution?
i tried that;
If theire is multiple copies of OCIW32.dll you have to make sure that there is only one copy of OCIW32.dll which should be in /Bin folder of the oracle home folder.
Add the IUSR_machine name account and the IWAM_machine name account to the Oracle home folder. Give both accounts full control.
Create empty file tnsnames.ora in same directory as aspnet_wp.exe,

Answer 1

Hi,
The issue doesnt make much sense on the surface at least. 12154 means the client couldnt figure out what you were referring to with your Data Source= entry. If the database was taken down, I'd expect an "oracle not available" or some other sort of error, as the client should have still be able to resolve the entry at least, even if the database wasnt up at the time.
What do you mean by "When i reset iis it start to work fine for a while.Then same problem occurs again."? The same problem meaning you get 12154 when you take the database down? Or you get 12154 without a db restart?
Are you using TNSNames.ora for client naming resolution, or something else (ldap, for example)?
Greg