I installed isconfig and added the mail domain as well as the DNS records correctly. However, when I try to log into squirrel mail on my website it gives an error. "Error connecting to IMAP server: localhost. 111 : Connection refused" is what it says. I have the IMAP server online and everything seems correct. How do I address this issue?
That depends on the Linux Distribution that you used. Which Tutorial did you use to install ISPConfig?