I keep getting the error: The server returned the error: The server “p04-imap.mail.me.com” cannot be contacted on port 993.

icloud email address that I have had since 2006. iMac 21.5-inch, Mid 2011

I keep getting: The server returned the error: The server “p04-imap.mail.me.com” cannot be contacted on port 993.

I go into preferences-accounts-advanced and untick the SSL box, I close mail, I reopen mail and tick the box again, close mail and the problem is fixed... for anywhere between a few minutes and a couple of days. Then I get the same error again.

Can anyone reccomend a more permanent fix for this issue?

Thanks,

R

iMac 21.5-inch, Mid 2011, 2.8 GHz Intel Core i7, 20 GB 1333 MHz DDR3, AMD Radeon HD 6770M 512 MB, OS X 10.8.4 (12E55)