ODP.NET Connection exception

This guy helped me solve my problem https://pravsdatums.wordpress.com/2013/12/16/ocac-12c-and-visual-studio-developer-tools/#comment-1

The solution was to remove LDAP from NAMES.DIRECTORY_PATH in the sql.ora file. This file is located on your client home directory (this path can be found on one of the key in the registry under HLM/SOFTWARE/ORACLE). So the content of the file went from

SQLNET.AUTHENTICATION_SERVICES= (none)

NAMES.DIRECTORY_PATH= (LDAP, TNSNAMES, EZCONNECT)

To

SQLNET.AUTHENTICATION_SERVICES= (none)

NAMES.DIRECTORY_PATH= (EZCONNECT, TNSNAMES)

And now it works ! I don't know why it was working on my development machine (maybe because Oracle is not installed on it).

Hope it can help somebody else !