go through the following steps :
a. Download the "Oracle Instant Client 11.1.0.6 - Basic Lite". b. unzip to any folder and copy the following files to your Visual Studio project root:
oci.dll
ociw32.dll
orannzsbb11.dll
oraocci11.dll
oraociicus11.dll
msvcr71.dll (not necessary, should be supplied with most Windows versions)
(the first five are the minimum needed for the Oracle Instant Client, the last is the microsoft common runtime they use.)
c. Download the ODAC 11 XCopy (the current version is 11.1.0.6) and unzip.
OraOps11w.dll - in the odp.net20 folder, goes in your project root.
(this file is what the Oracle.DataAccess.dll talks to and uses to work with the Instant Client files).
d. For compatibility with ClickOnce deployment, select these files in your project and make sure they are "Content" and "Copy Local" in your project. The manifest will then deploy them properly.
The following link describes the complete solution
http://stackoverflow.com/questions/923283/what-is-the-minimal-setup-required-to-deploy-a-net-application-with-oracle-clie[
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