diff --git a/agents/meshcore.js b/agents/meshcore.js
index 547b2f08..809057ad 100644
--- a/agents/meshcore.js
+++ b/agents/meshcore.js
@@ -4114,7 +4114,7 @@ function agentUpdate_Start(updateurl, updateoptions) {
                 agentUpdate_Start._selfupdate = null;
             });
             agentUpdate_Start._selfupdate.on('response', function (img) {
-                this._file = require('fs').createWriteStream(agentfilename + (process.platform == 'win32' ? '.update.exe' : 'update'), { flags: 'wb' });
+                this._file = require('fs').createWriteStream(agentfilename + (process.platform == 'win32' ? '.update.exe' : '.update'), { flags: 'wb' });
                 this._filehash = require('SHA384Stream').create();
                 this._filehash.on('hash', function (h) {
                     if (updateoptions != null && updateoptions.hash != null) {
diff --git a/agents/recoverycore.js b/agents/recoverycore.js
index 566378b0..f8b0207e 100644
--- a/agents/recoverycore.js
+++ b/agents/recoverycore.js
@@ -417,7 +417,7 @@ function agentUpdate_Start(updateurl, updateoptions) {
                 agentUpdate_Start._selfupdate = null;
             });
             agentUpdate_Start._selfupdate.on('response', function (img) {
-                this._file = require('fs').createWriteStream(agentfilename + (process.platform=='win32'?'.update.exe':'update'), { flags: 'wb' });
+                this._file = require('fs').createWriteStream(agentfilename + (process.platform=='win32'?'.update.exe':'.update'), { flags: 'wb' });
                 this._filehash = require('SHA384Stream').create();
                 this._filehash.on('hash', function (h) {
                     if (updateoptions != null && updateoptions.hash != null) {