On my Debian system with ISPConfig installed, i have installed Squirrelmail.
I have created a website webmail.mywebhostcompany.tld and Squirrelmail is installed in this website.
In my browser: when i point to URL http://webmail.mywebhostcompany.tld
, i see Squirrelmail's login screen.
When i try to login for the first time with a username and password, an error occurs:
Error opening ../data/default_pref
Could not create initial preference file!
../data/ should be writable by user www-data
Please contact your system administrator and report this error.
How can i solve this?