Before all please tell what you did to get this error ?
Second, please describe your environment abit.
For example, do you have access to imapd.config/php.ini ?
You may also post sqirrelmail config here.
# You can put comments anywhere you want to. They are effective for the
# rest of the line.
# this is in the format of <name> = <value>. Whitespace at the beginning
# and end of the lines is removed. Whitespace before and after the = sign
# is removed. Everything is case *insensitive*.
# Yes = True = On = 1
# No = False = Off = 0
Title = "IMAP"
# Which logfile group...
LogFile = maillog
# Only give lines pertaining to courier...
# I'm not sure if this is complete, especially for the new webmail daemon in 0.$
#but you will get at least all currently supported logs
*OnlyService = (imapd|imapd-ssl)