Oracle error 12154 while importing DMP file

My Setup

I'm running Windows 7 64-bit, using Oracle DB 11g R2 for Windows 64-bit. I have Oracle SQL Developer Release 3.0 (4.0.2.15.21) as the GUI for my database.

Question

I followed the instructions from this post on how to import an Oracle .DMP file. I issued this command into the command prompt: C:\>imp sys@dev/password12345 FROMUSER=FOOADMIN TOUSER=FOOADMIN file=c:\fooadmin.dmp full=yes

It then prompts me for a password in which I enter the correct one and then I receive this error:

IMP-00058: ORACLE error 12154 encountered
ORA-12154: TNS:could not resolve the connect identifier specified
IMP-00000: Import terminated unsuccessfully

Actual Question: How do I fix this error and be able to import the .dmp file successfully? Or what are some steps I can head towards to potentially get this working...?

My Files & What I've Done

I have looked through countless posts on this same issue. My tnsnames.ora, listener.ora, & sqlnet.ora are located in this directory: C:\oracle\product\11.2.0\dbhome\NETWORK\ADMIN

My connection in my tnsnames.ora file looks like this (I have also tried to put my computer name as the HOST, instead of 127.0.0.1)...

DEV =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
    )
  (CONNECT_DATA =
    (SERVER = DEDICATED)
    (SERVICE_NAME = DEV)
  )
 )

PATH Variables

I added the following to my PATH (I realize there may be some unnecessary item in there, I just wanted to be on the safe side. ):
C:\oracle\product\11.2.0\dbhome\bin;C:\oracle\product\11.2.0\client_1;C:\oracle\product\11.2.0\client_1\bin;%ORACLE_HOME%\bin;

I also created two more variables in my System Variables...

TNS_ADMIN C:\oracle\product\11.2.0\dbhome\NETWORK\ADMIN

TNS_NAMES C:\oracle\product\11.2.0\dbhome\NETWORK\ADMIN

Use this on Windows (three nested double quotes):

exp system/password_for_system@dev file=c:\fooadmin.dmp full=yes

imp """sys/password12345@dev as sysdba""" FROMUSER=FOOADMIN TOUSER=FOOADMIN file=c:\fooadmin.dmp

In general imp would work as intended with sys account, it is just not recommended. But exp with sys account could possibly produce inconsistent dump file silently. So it's better to avoid it, for example use system.

StackExchange Database Administrators Q#74365, answer score: 6