Installation and Upgrade > Windchill ESI > Installing and Configuring Windchill ESI in an ORACLE Applications Environment > Reviewing Requirements
  
Reviewing Requirements
Before you install Windchill ESI, review the following Windchill ESI requirements.
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To minimize the occurrence of known issues, you should obtain the latest Windchill ESI software and patches from the PTC software update website. Contact PTC Technical Support if you require assistance.
Windchill ESI Requirements
Windchill ESI requires a correctly installed version of Windchill PDMLink.
PTC provides a summary of the information on the products and operating systems certified with Windchill ESI, as well as language support and interoperability of PTC products and specific platforms in the Windchill Product Support Matrices. This information is available to you from the following link:
http://www.ptc.com/appserver/cs/doc/indexrefdoc.htmjsp
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Each TIBCO product might require you to apply certain patches to your operating system. Refer to the readme files accompanying each TIBCO product for details on required patches.
Oracle Applications Requirements
Windchill Enterprise Systems Integration supports Oracle Applications 12.1.1, 12.1.3, 12.2.4, 12.2.5, and 12.2.6. Earlier and later versions of Oracle Applications may include significant differences in functionality and API structures that will not be compatible with standard Windchill ESI. In these cases, customization of the solution may be required, or the target system may have to be classified as unsupported.
Windchill ESI requires the following Oracle Applications patches to be applied after your installation is complete:
For Oracle 12.1.1
8510589
8625817
8874286
9755255
8660792
9678667
For Oracle 12.1.3
9678667
1433613.1
12676077:R12.BOM.C
You can obtain the patches from the following Web site: http://metalink.oracle.com