I need delete the slqnet.ora on my oracle home.
And I obtain this error when I try connect in any database.

Information:
PL/SQL Developer
Version 9.0.1.1613
156.75334 - 10 user license
Windows 6.2 Build 9200
Language: Brazilian (Allround Automations)

Physical memory : 2.097.152 kB (2.097.152 available)
Paging file : 4.194.304 kB (3.327.356 available)
Virtual memory : 2.097.024 kB (1.814.800 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\gesif\AppData\Roaming\PLSQL Developer\Preferences\gesif\default.ini

Plug-Ins

Aliases
AGRALE_PROD
SYNPRD
SYNPRD_nova
SYNTST

Homes
OraClient11g_SYNCHRO (C:\Program Files\Synchro\oracleclient11\)
OraClient12Home3 (C:\oracle\12.1.0\client)

DLLs
C:\oracle\12.1.0\client\bin\oci.dll

TNS File
C:\Program Files\Synchro\oracleclient11\network\admin\tnsnames.ora

Using
Home: OraClient12Home3
DLL: C:\oracle\12.1.0\client\bin\oci.dll
OCI: version 11.1

Can you start PL/SQL Developer without connecting, go to Tools > Preferences > Oracle / Connection, select "OraClient11g_SYNCHRO" from the Oracle Home selection list, restart PL/SQL Developer, and try again?

It seems that the Oracle 12.1 Home that PL/SQL Developer is using now is not installed or configured properly.

Dont work bro

What exactly goes wrong with the OraClient11g_SYNCHRO home?

The same error. Look's like the program can't print the real error on screen. Can I see the logs in other place?

The error message cannot be retrieved by Oracle due to a language or language file issue.

Can you start PL/SQL Developer without connecting, go to Help > Support Info and send me the text from the "Info" tab page?

Infor:
PL/SQL Developer
Version 9.0.1.1613
156.75334 - 10 user license
Windows 6.2 Build 9200
Language: Brazilian (Allround Automations)

Physical memory : 2.097.152 kB (2.097.152 available)
Paging file : 4.194.304 kB (3.215.556 available)
Virtual memory : 2.097.024 kB (1.919.824 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:\Users\gesif\AppData\Roaming\PLSQL Developer\Preferences\default\Default.ini
C:\Users\gesif\AppData\Roaming\PLSQL Developer\Preferences\gesif\default.ini

Plug-Ins

Aliases
AGRALE_PROD
SYNPRD
SYNPRD_nova
SYNTST

Homes
OraClient11g_SYNCHRO (C:\Program Files\Synchro\oracleclient11\)
OraClient12Home3 (C:\oracle\12.1.0\client)

DLLs
C:\oracle\12.1.0\client\bin\oci.dll

TNS File
C:\Program Files\Synchro\oracleclient11\network\admin\tnsnames.ora

Using
Home: OraClient12Home3
DLL: C:\oracle\12.1.0\client\bin\oci.dll
OCI: version 11.1


Registry:
SOFTWARE\ORACLE
inst_loc = C:\Program Files\Oracle\Inventory
NLS_LANG = BRAZILIAN PORTUGUESE_BRAZIL.WE8MSWIN1252

SOFTWARE\ORACLE\JavaDeploy

SOFTWARE\ORACLE\KEY_OraClient11g_SYNCHRO
ORACLE_HOME = C:\Program Files\Synchro\oracleclient11\
ORACLE_HOME_NAME = OraClient11g_SYNCHRO
ORACLE_GROUP_NAME = Oracle - OraClient11g_SYNCHRO
NLS_LANG = AMERICAN_AMERICA.WE8MSWIN1252
OLEDB = C:\Program Files\Synchro\oracleclient11\oledb\mesg
OO4O = C:\Program Files\Synchro\oracleclient11\oo4o\mesg

SOFTWARE\ORACLE\KEY_OraClient11g_SYNCHRO\OLEDB
CacheType = Memory
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 = 10
MetaDataCacheSize = 0
DBNotifications = 0
DeferUpdChk = 0

SOFTWARE\ORACLE\KEY_OraClient11g_SYNCHRO\OO4O
CacheBlocks = 20
FetchLimit = 100
FetchSize = 4096
PerBlock = 16
SliceSize = 256
TempFileDirectory = c:\temp
OO4O_HOME = C:\Program Files\Synchro\oracleclient11\oo4o

SOFTWARE\ORACLE\KEY_OraClient12Home3
ORACLE_HOME = C:\oracle\12.1.0\client
ORACLE_HOME_NAME = OraClient12Home3
ORACLE_GROUP_NAME = Oracle - OraClient12Home3
NLS_LANG = BRAZILIAN PORTUGUESE_BRAZIL.WE8MSWIN1252
ORACLE_BUNDLE_NAME = Enterprise
OLEDB = C:\oracle\12.1.0\client\oledb\mesg
ORACLE_HOME_TYPE = 2
ORACLE_SVCUSER = AUTORIDADE NT\SERVI

I see that it is still using OraClient12Home3 instead of OraClient11g_SYNCHRO. Can you switch to OraClient11g_SYNCHRO as described above and try again?

Works now. Thanks a lot