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TNS-12500 TNS-12546 TNS-12560 TNS-00516 32-bit Windows Error: 5: Input/output error (Doc ID 1557213.1)

Last updated on SEPTEMBER 18, 2018

Applies to:

Oracle Net Services - Version and later
Information in this document applies to any platform.


Dedicated connections were failing with I/O error. Listener not able to spawn a oracle server process.

Connections to Windows database via TNS listener, start to fail reporting error code TNS-12500.

Bequeath connections on the server work fine

SQL*Plus: Release - Production on Tue May 21 13:56:24 2013

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ORA-12500: TNS:listener failed to start a dedicated server process

Listener log shows full error stack for failing connection as:

21-MAY-2013 14:06:10 * (CONNECT_DATA=(SERVER=DEDICATED)(SID=DMS)(CID=(PROGRAM=E:\oracle\ora92\bin\sqlplus.exe)(HOST=myhostname)(USER=ghantak))) * (ADDRESS=(PROTOCOL=tcp)(HOST=XX.XXX.X.XX)(PORT=3914)) * establish * DMS * 12500
TNS-12500: TNS:listener failed to start a dedicated server process
TNS-12546: TNS:permission denied
 TNS-12560: TNS:protocol adapter error
  TNS-00516: Permission denied
   32-bit Windows Error: 5: Input/output error 


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