When you install Plesk 9 with all the features it enables SSO by default. When you login to the Plesk control panel and enable the firewall module you will then get locked out of Plesk when you disconnect. You won’t be able to login and may just be presented with a “Continue” button which will then time out.
URL: http://kb.parallels.com/en/5481
You can set the firewall to allow access to another port (SSO port), or, you can disable SSO with:
/usr/local/psa/bin/sso --disable
or
%pleskroot%/admin/bin/sso –d
just what i was looking for, its a shame plesk couldnt say that instead of saying just type in ./sso ???? which is of course wrong.
Many thanks for this, much appretiated and ended a string of problems for myself