IMAP command dialog box

IMAP command dialog box

I am receiving this error as I receive emails.  Why does this happen and how can I eliminate it? 

Your IMAP command could not be sent to the server, due to non-network errors. This could, for example, indicate a lack of memory on your system.

Configuration:
   Account: Radiocrystalblue (dan)
   Server: imap.zoho.com
   User name: dan@radiocrystalblue.net
   Protocol: IMAP
   Port: 993
   Secure(SSL): 1
   Code: 800ccc0f