binding issues - ldap monitor

I have set up an ldap monitor for a pool using TCP 636.

No matter what I do, it doesn't work.

I set up the user name: cn=username,ou=xxx,dc=yyy

set the password

set the Base: ou=xxx,dc=yyy

set a filter: filtername=username

I have tried setting it with all ports and with port 636 and even the standard ldap port (389). Also tried without the base, and also with no base and no filter.

No matter what I try, the debug log keeps showing :

Bind failed with username(-1): Can't contact LDAP server

What am I missing? 

This isn't an active directory ldap - so maybe this is the issue?

Any ideas would be very much appreciated.

Thanks,

Vered