I recently switched over to Windows 7 Enterprise 32 bit. I reinstalled PL/SQL Developer version 9.0.6.1665. I could have swarn that I got everything working last week, but when I tried to login today using TNS names, I get the following error: ORA-12154: TNS: could not resolve the connect identifier specified.

Support Info Below.

--- Info ---

PL/SQL Developer
Version 9.0.6.1665
01.80170 - 5 user license
Windows 7 6.1 Build 7601 (Service Pack 1)

Physical memory : 2,061,636 kB (863,448 available)
Paging file : 4,123,272 kB (2,163,468 available)
Virtual memory : 2,097,024 kB (1,960,616 available)

Parameters
C:\Program Files\PLSQL Developer\PlSqlDev.exe

Preferences
Session mode: Multi
OCI Library:
Use OCI7: False
Allow Multiple Connections: True

Preference Files
C:\Program Files\PLSQL Developer\Preferences\Default\Default.ini
C:\Users\239507\AppData\Roaming\PLSQL Developer\Preferences\239507\default.ini

Plug-Ins
*Active Query Builder (C:\Program Files\PLSQL Developer\PlugIns\ActiveQueryBuilder.dll)
*PL/SQL Documentation (plsqldoc) (C:\Program Files\PLSQL Developer\PlugIns\plsqldoc.dll)
*Red Gate Deployment Plug-In (C:\Program Files\PLSQL Developer\PlugIns\RedGate.dll)
*Version Control Interface 1.2 (C:\Program Files\PLSQL Developer\PlugIns\VCS.dll)
(* is Active)

Aliases
devl
func1
Fyec
IFACTI
IFACTI1
...

Homes
OraClient11g_home1 (C:\oracle\product\11.2.0\client_1)

DLLs
C:\oracle\product\11.2.0\client_1\bin\oci.dll

TNS File
C:\oracle\product\11.2.0\client_1\Network\Admin\tnsnames.ora

Using
Home: OraClient11g_home1
DLL: C:\oracle\product\11.2.0\client_1\bin\oci.dll
OCI: version 11.1

--- Registry ---

SOFTWARE\ORACLE
inst_loc = C:\Program Files\Oracle\Inventory

SOFTWARE\ORACLE\KEY_OraClient11g_home1
ORACLE_HOME = C:\oracle\product\11.2.0\client_1
ORACLE_HOME_NAME = OraClient11g_home1
ORACLE_GROUP_NAME = Oracle - OraClient11g_home1
ORACLE_BUNDLE_NAME = Enterprise
NLS_LANG = AMERICAN_AMERICA.WE8MSWIN1252
OLEDB = C:\oracle\product\11.2.0\client_1\oledb\mesg
OO4O = C:\oracle\product\11.2.0\client_1\oo4o\mesg
ORACLE_HOME_KEY = SOFTWARE\ORACLE\KEY_OraClient11g_home1

SOFTWARE\ORACLE\KEY_OraClient11g_home1\OLEDB
CacheType = Memory
EnableCmdTimeout = 0
ChunkSize = 100
DistribTX = 1
FetchSize = 100
OSAuthent = 0
PLSQLRset = 0
PwdChgDlg = 1
SchRstLng = 10000
UserDefFn = 0
DisableRetClause = 1
VCharNull = 1
TraceCategory = 0
TraceFileName = c:\OraOLEDB.trc
TraceLevel = 0
TraceOption = 0
SPPrmDefVal = 0
StmtCacheSize = 0
MetaDataCacheSize = 0
DBNotifications = 0
DeferUpdChk = 0

SOFTWARE\ORACLE\KEY_OraClient11g_home1\OO4O
CacheBlocks = 20
FetchLimit = 100
FetchSize = 4096
HelpFile = C:\oracle\product\11.2.0\client_1\oo4o\doc\oraclec.chm
PerBlock = 16
SliceSize = 256
TempFileDirectory = c:\temp
OO4O_HOME = C:\oracle\product\11.2.0\client_1\oo4o

SOFTWARE\ORACLE\ODP.NET

SOFTWARE\ORACLE\ODP.NET\2.112.1.0
DllPath = C:\oracle\product\11.2.0\client_1\bin
TraceFileName = C:\odpnet2.trc
TraceLevel = 0
TraceOption = 0
PromotableTransaction = promotable
SelfTuning = 1
StatementCacheWithUdts = 1
UdtCacheSize = 4096
PerformanceCounters = 0
MaxStatementCacheSize = 100
DemandOraclePermission = 0

--- Path ---

C:\oracle\product\11.2.0\client_1\bin
C:\Program Files\CA\DCS\CAWIN\
C:\Program Files\Business Objects\Common\3.5\bin\NOTES\
C:\Program Files\Business Objects\Common\3.5\bin\NOTES\DATA\
C:\Windows\system32
C:\Windows
C:\Windows\System32\Wbem
C:\Windows\System32\WindowsPowerShell\v1.0\
C:\Program Files\Microsoft Application Virtualization Client
C:\Program Files\IBM\Personal Communications\
C:\Program Files\IBM\Trace Facility\
c:\Program Files\IBM\Client Access\Emulator
c:\Program Files\IBM\Client Access\Shared
c:\Program Files\IBM\Client Access\
C:\Windows\ESISOFT
C:\Program Files\Internet Explorer
C:\SQLLIB\BIN
C:\SQLLIB\FUNCTION
C:\Program Files\CheckPoint\File Encryption\Program\

--- TNS names ---

#8:03 AM 5/30/2012# TNSNAMES.ORA Network Configuration File: c:\orant91\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.
# Last Updated 11/17/2009
# 5/30/12 - replace s0b1205.ssa.gov With s0b1205.ba.ssa.gov
# 5/30/12 - replace s0b1206.ssa.gov With s0b1206.ba.ssa.gov

devl=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=dsel-u0211.ssa.gov)(PORT=1531))
(CONNECT_DATA=
(SID=devl)
)
)


IFACTI=
(DESCRIPTION=
(ADDRESS_LIST=
(LOAD_BALANCE=YES)
(FAILOVER=YES)
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1200-vip.ssa.gov)(PORT=55000))
)
(CONNECT_DATA=
(SERVICE_NAME=IFACTI)
)
)


IFACTI1=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1200-vip.ssa.gov)(PORT=55000))
(CONNECT_DATA=
(SERVICE_NAME=IFACTI)
(INSTANCE_NAME=IFACTI1)
)
)

IFACTI2=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1201-vip.ssa.gov)(PORT=55000))
(CONNECT_DATA=
(SERVICE_NAME=IFACTI)
(INSTANCE_NAME=IFACTI2)
)
)


PRFACT01=
(DESCRIPTION=
(LOAD_BALANCE=YES)
(FAILOVER=YES)
(ADDRESS_LIST=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1202-vip.ssa.gov)(PORT=55000))
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1203-vip.ssa.gov)(PORT=55000))
)
(CONNECT_DATA=
(SERVICE_NAME=prfact01)
)
)


VFACTI=
(DESCRIPTION=
(ADDRESS_LIST=
(LOAD_BALANCE=YES)
(FAILOVER=YES)
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1200-vip.ssa.gov)(PORT=10910))
)
(CONNECT_DATA=
(SERVICE_NAME=VFACTI)
)
)



sandold=
(DESCRIPTION=
(ADDRESS_LIST=
(LOAD_BALANCE=YES)
(FAILOVER=YES)
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1206-vip.ssa.gov)(PORT=1550))
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1205-vip.ssa.gov)(PORT=1550))
)
(CONNECT_DATA=
(SERVICE_NAME=sand)
)
)

sand2=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1205.ba.ssa.gov)(PORT=1550))
(CONNECT_DATA=
(SERVICE_NAME=sand)
(INSTANCE_NAME=sand2)
)
)




vtest=
(DESCRIPTION=
(ADDRESS_LIST=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1206.ba.ssa.gov)(PORT=1566))
)
(CONNECT_DATA=
(SID=vtest2)
)
)



VTESTold=
(DESCRIPTION=
(ADDRESS_LIST=
(LOAD_BALANCE=YES)
(FAILOVER=YES)
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1205-vip.ssa.gov)(PORT=1566))
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1206-vip.ssa.gov)(PORT=1566))
)
(CONNECT_DATA=
(SERVICE_NAME=vtest)

)
)



UTEST=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=dsel-u0211.ssa.gov)(PORT=1536))
(CONNECT_DATA=
(SID=utest)
)
)



tech2=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1206.ba.ssa.gov)(PORT=1572))
(CONNECT_DATA=
(SERVICE_NAME=tech2)
(INSTANCE_NAME=tech2)
)
)



Fyec=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=dsel-u0211.ssa.gov)(PORT=1581))
(CONNECT_DATA=
(SID=Fyec)
)
)

func1=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1206-vip.ssa.gov)(PORT=1555))
(CONNECT_DATA=
(SERVICE_NAME=func)
(INSTANCE_NAME=func1)
)
)



tppsdev = (DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1205.ba.ssa.gov)(PORT=1591))
(CONNECT_DATA=(SID=tppsdev))
)


tte1=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=s0b1206.ba.ssa.gov)(PORT=1591))
(CONNECT_DATA=
(SID=te1)
)
)