I have problem with SMF 2.0 B4 PLz help me

[doing007]

Hi iam using SMF 2.0 beta 4 , install and everything is fine but recently i am facing error when i Loged in to my site

Error is

!!
Performance Warning
The cache directory is not writable - this will adversely affect the performance of your forum.

But this error is happening when i logged using my Admin user name and password
if i Logged in using a another member (Norman register user) it's not showing this error
now i am suffering with error. can any one tell me how to rectify this error
Thanks

[SlammedDime]

FTP to your site, and set the cache directory permissions to 777.

Regular users will not see this message because it is not meant for them, it is meant for admins to tell them something is wrong.