Cache and and Run Workflow option is grayed out.

[CherieACI]

Earlier today I learned about the cache and run workflow option but now as I am trying to use it the option is grayed out in the menu and won't let me select it. Why is that? 

[PhilipMannering]

That may be either because you are attempting to cache on a tool that has multiple outputs. 

Or because your workflow joins on to itself downstream. 

Try caching at the end of your workflow on something simple like a Select Tool with single output anchor.

[Qiu]

@CherieACI 
Just add to @PhilipMannering , below the a few things we need to know about Cache.

https://community.alteryx.com/t5/Engine-Works/Just-take-the-Cache-and-Run-Caching-in-2018-3/ba-p/306...