diff --git a/devtools/deployments/shared/config/ldap/schemas/20_opencloud_education_schema.ldif b/devtools/deployments/shared/config/ldap/schemas/20_opencloud_education_schema.ldif
index af29747456..8e5e5e9b70 100644
--- a/devtools/deployments/shared/config/ldap/schemas/20_opencloud_education_schema.ldif
+++ b/devtools/deployments/shared/config/ldap/schemas/20_opencloud_education_schema.ldif
@@ -42,4 +42,4 @@ olcObjectClasses: ( openCloudOid:1.2.5 NAME 'openCloudEducationSchool'
   DESC 'OpenCloud education school objectclass'
   SUP openCloudObject
   AUXILIARY
-  MAY ( openCloudEducationSchoolNumber $ openCloudEducationSchoolTerminationTimestamp ) )
+  MAY ( openCloudEducationSchoolNumber $ openCloudEducationSchoolTerminationTimestamp $ openCloudEducationExternalId) )
diff --git a/services/graph/pkg/identity/ldap.go b/services/graph/pkg/identity/ldap.go
index 673ade1bb1..fd0fa3d656 100644
--- a/services/graph/pkg/identity/ldap.go
+++ b/services/graph/pkg/identity/ldap.go
@@ -80,6 +80,7 @@ type LDAP struct {
 type userAttributeMap struct {
 	displayName    string
 	id             string
+	externalId     string
 	mail           string
 	userName       string
 	givenName      string
diff --git a/services/graph/pkg/identity/ldap_education_class.go b/services/graph/pkg/identity/ldap_education_class.go
index a45e01e238..bec54aee11 100644
--- a/services/graph/pkg/identity/ldap_education_class.go
+++ b/services/graph/pkg/identity/ldap_education_class.go
@@ -7,8 +7,8 @@ import (
 
 	"github.com/go-ldap/ldap/v3"
 	"github.com/libregraph/idm/pkg/ldapdn"
-	"github.com/opencloud-eu/opencloud/services/graph/pkg/errorcode"
 	libregraph "github.com/opencloud-eu/libre-graph-api-go"
+	"github.com/opencloud-eu/opencloud/services/graph/pkg/errorcode"
 )
 
 type educationClassAttributeMap struct {
@@ -349,6 +349,7 @@ func (i *LDAP) getEducationClassByID(nameOrID string, requestMembers bool) (*lda
 	return i.getEducationObjectByNameOrID(
 		nameOrID,
 		i.userAttributeMap.id,
+		i.userAttributeMap.externalId,
 		i.educationConfig.classAttributeMap.externalID,
 		i.groupFilter,
 		i.educationConfig.classObjectClass,
diff --git a/services/graph/pkg/identity/ldap_education_user.go b/services/graph/pkg/identity/ldap_education_user.go
index c2700195ed..bf58f43c79 100644
--- a/services/graph/pkg/identity/ldap_education_user.go
+++ b/services/graph/pkg/identity/ldap_education_user.go
@@ -318,6 +318,7 @@ func (i *LDAP) getEducationUserAttrTypes() []string {
 	return []string{
 		i.userAttributeMap.displayName,
 		i.userAttributeMap.id,
+		i.userAttributeMap.externalId,
 		i.userAttributeMap.mail,
 		i.userAttributeMap.userName,
 		i.userAttributeMap.surname,
@@ -345,6 +346,7 @@ func (i *LDAP) getEducationUserByNameOrID(nameOrID string) (*ldap.Entry, error)
 		nameOrID,
 		i.userAttributeMap.userName,
 		i.userAttributeMap.id,
+		i.userAttributeMap.externalId,
 		i.userFilter,
 		i.educationConfig.userObjectClass,
 		i.userBaseDN,
@@ -352,9 +354,9 @@ func (i *LDAP) getEducationUserByNameOrID(nameOrID string) (*ldap.Entry, error)
 	)
 }
 
-func (i *LDAP) getEducationObjectByNameOrID(nameOrID, nameAttribute, idAttribute, objectFilter, objectClass, baseDN string, attributes []string) (*ldap.Entry, error) {
+func (i *LDAP) getEducationObjectByNameOrID(nameOrID, nameAttribute, idAttribute, externalIdAttribute, objectFilter, objectClass, baseDN string, attributes []string) (*ldap.Entry, error) {
 	nameOrID = ldap.EscapeFilter(nameOrID)
-	filter := fmt.Sprintf("(|(%s=%s)(%s=%s))", nameAttribute, nameOrID, idAttribute, nameOrID)
+	filter := fmt.Sprintf("(|(%s=%s)(%s=%s)(%s=%s)", nameAttribute, nameOrID, idAttribute, nameOrID, externalIdAttribute, nameOrID)
 	return i.getEducationObjectByFilter(filter, baseDN, objectFilter, objectClass, attributes)
 }