Tine uses the Zend Framework LDAP adapter, so a good place to refer to is the Zend LDAP documentation Adapter and here LDAP API

LDAP Settings

This works for OpenLDAP. For authorizing against an ADS, check the documentation mentioned above.
The "Initial Admin User" you have to specify during setup, will be the tine-administrator, you can not use your LDAP admin. Unless you already have such an extraadminaccount, you have to create this account. Recommended objectClass: posixAccount; but you need a structural objectClass too: InetOrgPerson (use "uid" as RDN, because tine will save all accounts with this RDN, looks nicer).

For using LDAP as accountstorage, you need to create your groups too; objectClass: posixGroup

minimal LDAP prerequirements should look like this:

• ou=user,dc=abc,dc=de
  • uid=admin (posixAccount,InetOrgPerson)
• ou=groups,dc=abc,dc=de
  • cn=administrators (posixGroup)
    • memberuid=admin
  • cn=users (posixGroup)

Take care, that the gidNumber, uidNumber and Groupnames you specify in your LDAP match these in your tinesetup!

Here's an example of a working configuration

as UUID attribute for accounts/groups: stay with the standard "entryUUID".