the 6413 error is commonly caused when a directory containing brackets is used - like in your case (DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=server)(PORT=1521)))(CONNECT_DATA=(SID=CRONUS)(CID=(PROGRAM=C:\Program Files (x86)\Common Files\Microsoft Shared\DevServer\9.0\WebDev.WebServer.EXE)(HOST=SEDNA)(USER=x))))
where the CID contains C:\Program Files (x86).
Not sure which OCI/Client release you are using, but in general the latest releases should contain this fix.
Not sure as i haven't tried it, but maybe a link for the executable might solve the issue as well.
If nothing works for your case, then yes, you have to reinstall.
Edited by: kgronau on Mar 21, 2011 2:10 PM
Have a look also at "My Oracle Support" note:
Connecting to Oracle from Within Visual Studio Fails With: ORA-12154 or ORA-6413, While Compiled Applications Run Fine (Doc ID 334968.1)
The executable module of your application has been placed into folder "C:\Program Files (x86)\..." while Oracle does not allow bracket symbols in client application. This could be very possible reason of the error mentioned in yout post. Try to re-install the application into another location that does not contain brackets in the path.
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