I have a Server 2008 R2 server with ADDS installed. I'm trying to configure HP's ILO utility to connect to it over SSL. I installed the Active Directory Certificate Service, after doing so I'm still not able to connect to LDAP over SSL.
I checked the event log and it's showing warnings with Event ID 36886 saying that there aren't default credentials yet. I'm not too sure why this is happening. I haven't done anything with ADCS other than installing the service do I need to create a certificate for the server?
You don't have a server certificate to use with LDAP. This is exactly what the event log is telling you. Installing Certificate Service will not create a certificate for you, this is an explicit step you need to do.
How to get a certificate for your LDAP server will depend on whether you plan to deploy your own PKI (using Certificate Services) or just use a 3rd party certificate. If you are not familiar with this, you need to do some research and pick which way to go. The former is harder and more error prone, but most flexibe and the latter is easy to get going but not very flexible.