HAS,
The last version that was TESTED with the ISA plugin was version 11.6.X.
The ISA plugin was an ADD-ON piece to the actual Windows ISA server, so it really is not a portion of the DLP Architecture per say. That plug-in was just an ICAP protocol plugin tha was installed on top of the ISA server. This just allowed DLP to be able to communicate with ISA using the ICAP protocol, which is what Web Prevent needs to use (ICAP).
So the ISA plugin is just an add-on protocol of ICAP and should still work with ANY version of DLP Web Prevent.
Here is the description of the plugin: Microsoft Internet Security and Acceleration Server (ISA) is a security gateway product that provides both a firewall service and a Web proxy service. ISA provides no native Internet Content Adaptation Protocol (ICAP) interface, which is necessary to integrate Symantec Data Loss Prevention Network Prevent for Web with the Web proxy. However, ISA provides a Web filter architecture that enables third parties to process Web requests and responses as they are proxied
See the enclosed document on how to configure the ICAP Add-on.
It should work.. with no issues.
Hope this makes sense.
If this solves your questions please marked as solved.
Ronak