diff --git a/helmfile/apps/nubus/values-nubus.yaml.gotmpl b/helmfile/apps/nubus/values-nubus.yaml.gotmpl
index fcbd6dfc..9186a203 100644
--- a/helmfile/apps/nubus/values-nubus.yaml.gotmpl
+++ b/helmfile/apps/nubus/values-nubus.yaml.gotmpl
@@ -4,6 +4,12 @@
 additionalAnnotations:
   {{ .Values.annotations.nubus.additional | toYaml | nindent 2 }}
 
+# -- Disable the cert-manager resources from the Helm chart if certificates are deactivated
+{{- if not .Values.apps.certificates.enabled }}
+certificates:
+  enabled: False
+{{- end }}
+
 global:
   certManagerIssuer: {{ .Values.certificate.issuerRef.name | quote }}
   domain: {{ .Values.global.domain | quote }}
@@ -1521,6 +1527,12 @@ nubusUmcServer:
   smtp:
     auth:
       password: {{ .Values.secrets.postfix.opendeskSystemPassword | quote }}
+{{- if .Values.certificate.selfSigned }}
+  extraVolumes:
+    - name: "certificates"
+      secret:
+        secretName: "opendesk-certificates-tls"
+{{- end }}
 
 nubusUmcGateway:
   containerSecurityContext: