The following is if you're using customapache. If you're using custombuild, see below.
If you cannot login to roundcube because you get this error:
DATABASE ERROR: CONNECTION FAILED!
Then do the following:
Type:
cat /usr/local/directamin/conf/mysql.conf
to get the login/password for mysql.
Type:
mysql -uda_admin -ppassword
where da_admin/password are the login/pass output from the mysql.conf.
Once in mysql, type:
DROP DATABASE da_roundcube;
quit once the db is dropped and you're out of mysql, type:
cd /usr/local/directadmin/scripts ./roundcube.sh
to recreate the database and user/pass for roundcube.
The following is the fix if you're using custombuild:
cd /usr/local/directadmin/custombuild ./build roundcube