I have installed Oracle9i and Developer6i on my system. It connects to the database with the hostname but when I connect to forms it gives 'packet writer failure' TNS : 12571 ERROR. I deinstalled McAfee firewall but still it gives me the same error. When I tnsping my hostname it pings from command prompt, but when I connect through Forms6i it gives TNS 12571 error message.
TNS Ping Utility for 32-bit Windows: Version 184.108.40.206.0 - Production on 12-MAY-2004 21:31:54
Copyright (c) 1997 Oracle Corporation. All rights reserved.
Used parameter files:
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = prahlad)(PORT = 1521))) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = oracle))) OK (470 msec)
I have problems executing Forms.
There are many possible scenarios that raise the TNS-12571 error. Your firewall software is one likely reason, but there are many, many others. The tnsping output suggests that you are attempting to connect to a database service with SERVICE_NAME "oracle" which seems like an odd name to use. You may want to make sure that the tnsnames entry is correct.
The times I've encountered the packet writer failure have always been problems related to an underlying networking issue. If your host is connected to a network where you do not get a static IP address, and you just need to connect locally, then consider using the localhost name or address of 127.0.0.1 since that will always connect you locally.
If all else fails, use trace_level_client = 16 to turn on tracing on your client and attempt to make a connection. There's a lot of information pumped out in a SQL*Net trace at level 16, but the root cause to your problem and the explanation about why SQL*Net is failing will be in there somewhere. Check Metalink for more information about enabling SQL*Net tracing.