Well you need to have ssl configured on your web-server first... then check that you can connect to your webERP installation using the
https://yourdomain.com/webERP - once this is possible you can set the configuration parameter to require connections only over ssl.
If you wish to set this parameter back and you don't have ssl configured for your web-server (it is impossible to connect to webERP now!!) you need to go into phpMyAdmin or other mysql client and run the following SQL
Code:
UPDATE config SET confvalue='0' WHERE confname='HTTPS_Only';