error 12541 - strange error on TNS: no listener

been getting a strange error here,

I have my Tnsnames.ora file all setup, and I can connect to all the databases on my server fine using SQL Plus, Enterprise Manager, SQL Plus Worksheet and by "testing" the connection inside of Net Manager. However, once i try doing an import or export (using exp/imp commands) I get a

EXP-00056: ORACLE error 12541 encountered
ORA-12541: TNS:no listener
EXP-00000: Export terminated unsuccessfully

It even gets stranger.. Using an application developed in Powerbuilder.... When running off of source code, it can connect to the database fine. However, if I compile the code into exe and run off of there, i get the No Listener error. They both connect using the Oracle native driver and read how to connect off of the same ini file.

No-one else in my office has this problem. What could be wrong with my setup? Any help appreciated

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Luciano Belotto
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