Share Session State Across Multiple Domains in .net ( NOT SUB Domains )
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I am using ASP.net 3.5 w/ C# using SQL Server with Session State stored in the SQL Server DB. 

I have an issue with losing session state across multiple domains, but using the same browser instance and same code base.

For example, We are directing customers to **www.MyStore.com** to browse our store and we want to send customers to **www.MyStore.ShopPlatform.com** to checkout w/ secure SSL validation.  The session is being re-created when re-directed to **www.MyStore.ShopPlatform.com**.

The wildcard SSL is installed at www.ShopPlatform.com.

So, The question is.... How do you associate 1 session state cookie to multiple domains (**www.MyStore.com**  and **www.MyStore.ShopPlatform.com**) on the same server using .net?