diff --git a/management/univention-appcenter/ldap/66univention-appcenter_app.acl b/management/univention-appcenter/ldap/66univention-appcenter_app.acl
index 24c4cef..9685d5f 100644
--- a/management/univention-appcenter/ldap/66univention-appcenter_app.acl
+++ b/management/univention-appcenter/ldap/66univention-appcenter_app.acl
@@ -2,7 +2,9 @@
 params = {}
 params['base'] = configRegistry['ldap/base']
 
-print '''
+import os.path
+if os.path.exists('/var/lib/univention-ldap/local-schema/univention-app.schema'):
+	print '''
 access to dn.regex="^univentionAppID=([^,]+),cn=([^,]+),cn=apps,cn=univention,%(base)s$" filter="(objectClass=univentionApp)" attrs=entry,@univentionApp,@univentionObject
 	by dn.onelevel="cn=dc,cn=computers,%(base)s" write
 	by dn.onelevel="cn=memberserver,cn=computers,%(base)s" write
diff --git a/virtualization/univention-virtual-machine-manager-schema/conffiles/etc/ldap/slapd.conf.d/66univention-ldap-server_acl-master-uvmm b/virtualization/univention-virtual-machine-manager-schema/conffiles/etc/ldap/slapd.conf.d/66univention-ldap-server_acl-master-uvmm
index 00708a1..2744acd 100644
--- a/virtualization/univention-virtual-machine-manager-schema/conffiles/etc/ldap/slapd.conf.d/66univention-ldap-server_acl-master-uvmm
+++ b/virtualization/univention-virtual-machine-manager-schema/conffiles/etc/ldap/slapd.conf.d/66univention-ldap-server_acl-master-uvmm
@@ -2,8 +2,10 @@
 params = {}
 params['right'] = 'write' if configRegistry['ldap/server/type'] == 'master' else 'read'
 params['base'] = configRegistry['ldap/base']
+import os.path
 
-print '''
+if os.path.exists('/usr/share/univention-ldap/schema/univention-virtual-machine-manager.schema'):
+	print '''
 access to dn.regex="^univentionVirtualMachineUUID=([^,]+),cn=Information,cn=Virtual Machine Manager,%(base)s$" filter="(objectClass=univentionVirtualMachine)" attrs=entry,@univentionVirtualMachine,@univentionObject
 	by dn.onelevel="cn=dc,cn=computers,%(base)s" %(right)s
 	by dn.onelevel="cn=memberserver,cn=computers,%(base)s" %(right)s