When running a query on a table in Access using a Data Source ODBC, users may periodically get an ODBC error: "ORA-12154:  TNS could not resolve the connect identifier specified". 

The first thing to check is to make sure you have access to \\iowa.uiowa.edu\shared\uidata\psoft\oracle.  If you can access this directory, move on to the next step. 

The second thing to check is to make sure that you do not have a conflict between a User DSN and a System DSN.  You should have one System DSN with the data source name set to DWPROD and the TNS service name set to dwprod.world as shown below.  It should be using the Oracle in OraClient 11g_home#.  Do NOT select Microsoft ODBC drivers.  To get to this, go to Control Panel, Administrative Tools and Data Sources ODBC. 

If you have dwprod listed as a User DSN, rename it by click on "Configure" and then rename it to dwprod_old.