diff --git a/nodes/core/core/75-exec.js b/nodes/core/core/75-exec.js
index a3c5f7420..8c461e34b 100644
--- a/nodes/core/core/75-exec.js
+++ b/nodes/core/core/75-exec.js
@@ -37,7 +37,7 @@ module.exports = function(RED) {
                 if (typeof(msg.payload !== "string")) { msg.payload = (msg.payload || "").toString(); }
                 var arg = [];
                 if (node.append.length > 0) { arg = node.append.split(","); }
-                if ((node.addpay === true) && (msg.payload.trim() !== "")) { arg.unshift(msg.payload); }
+                if ((node.addpay === true) && (msg.payload.toString().trim() !== "")) { arg.unshift(msg.payload); }
                 if (RED.settings.verbose) { node.log(node.cmd+" ["+arg+"]"); }
                 if (node.cmd.indexOf(" ") == -1) {
                     var ex = spawn(node.cmd,arg);
@@ -67,7 +67,7 @@ module.exports = function(RED) {
             }
             else {
                 var cl = node.cmd;
-                if ((node.addpay === true) && ((msg.payload || "").trim() !== "")) { cl += " "+msg.payload; }
+                if ((node.addpay === true) && ((msg.payload.toString() || "").trim() !== "")) { cl += " "+msg.payload; }
                 if (node.append.trim() !== "") { cl += " "+node.append; }
                 if (RED.settings.verbose) { node.log(cl); }
                 var child = exec(cl, {encoding: 'binary', maxBuffer:10000000}, function (error, stdout, stderr) {