Yes, I have really tried to install squirrelmail a day or two ago, but when i wanted to login using squirrelmail interface, it said that my imap server does not allow plain text logins or something like that.
Bad request: The IMAP server is reporting that plain text logins are disabled. Using CRAM-MD5 or DIGEST-MD5 authentication instead may work.
Also, the use of TLS may allow SquirrelMail to login. Please contact your system administrator and report this error.
What can solve that problem?