diff --git a/certoperations.js b/certoperations.js
index 9202e444..dc173b8b 100644
--- a/certoperations.js
+++ b/certoperations.js
@@ -180,7 +180,7 @@ module.exports.CertificateOperations = function (parent) {
                 } else if ((typeof acmconfig.certfiles == 'object') && (typeof acmconfig.keyfile == 'string')) {
                     // PEM format, certfiles and keyfile
                     r = { certs: [], keys: [] };
-                    for (var k in acmconfig.certfiles) { r.certs.push(obj.pki.certificateFromPem(obj.fs.readFileSync(obj.common.joinPath(obj.parent.datapath, acmconfig.certfiles[k])))); }
+                    for (var k in acmconfig.certfiles) { r.certs.push(obj.pki.certificateFromPem(obj.fs.readFileSync(parent.common.joinPath(obj.parent.datapath, acmconfig.certfiles[k])))); }
                     r.keys.push(obj.pki.privateKeyFromPem(obj.fs.readFileSync(obj.parent.joinPath(obj.parent.datapath, acmconfig.keyfile))));
                     if ((r.certs.length < 2) || (r.keys.length != 1)) continue;
                 }