Relocating disk cache to separate hard drive, error message.

[Evie5C4A]

I am new to after effects, and have been working on a project which over time has become almost impossible to work on due to the amount of time it takes to render and playback. 

Ive tried clearing as much space on my laptop and thought it might be wise to purchase a 1TB hardrive and relocate my disk cache or media cache to it, but each time i try it produces an error:

As i am new to after effects, any suggestions on how to do this or speed up rendering/ playback would be greaty appreciated! 

[Mylenium]

It means what it says. Simply create folder on the external drive to place the cache in.

Mylenium

[Evie5C4A]

Ah thanks that worked! As i say, im new to AE so very appreciated.