diff --git a/index.js b/index.js
index 7c4c5cc..6cd8ab9 100644
--- a/index.js
+++ b/index.js
@@ -23,9 +23,12 @@ zip.listFileContents(FILENAME, (entries) => {
   let osguess1 = osguess.guessFromFilename(FILENAME);
   let osguess2 = osguess.guessFromContents(entries);
 
-  if (osguess1 !== osguess2 && osguess1!==null) {
+  if (osguess1 !== osguess2 && osguess1 && osguess2) {
     console.log(`Unsure about operating system. Going with ${osguess2}. Other option was ${osguess1}`);
   }
+  if (osguess1 && !osguess2) {
+    osguess2 = osguess1
+  }
   let arch = osguess.guessArch(FILENAME, entries);
   let asar = finder.asar(entries);
   let binary = finder.binary(entries);
@@ -54,8 +57,8 @@ zip.listFileContents(FILENAME, (entries) => {
   if (versionFiles.length > 0) {
     versionFiles.map((f) => {
       zip.readFileContents(FILENAME, f, (c) => {
-        console.log("Found Version file: v" + c);
-        logSupport(`v${c}`)
+        console.log("Found Version file: " + c);
+        logSupport(`${c}`)
       });
     });
   }
diff --git a/os.js b/os.js
index ffb97de..52919b9 100644
--- a/os.js
+++ b/os.js
@@ -14,12 +14,10 @@ module.exports = {
 		} else if (fn.match(/win/)) {
 			return 'win32'
 		} else {
-			ext = path.extname(inputFile)
-			if (ext.match(/dmg/)) {
-				return 'darwin'
-			} else if (ext.match('/exe/')) {
-				return 'win32'
-			} else if (ext.match(/deb/) ||ext.match(/appimage/i) || ext.match(/pacman/)) {
+			let ext = path.extname(inputFile).toLowerCase()
+      if (ext == '.dmg') {return 'darwin'}
+      if (ext == '.exe') {return 'win32'}
+      if (['.deb', '.appimage', '.pacman'].indexOf(ext) !== -1) {
         return 'linux'
       }
 		}
diff --git a/tests/os.js b/tests/os.js
index 020e474..78928f0 100644
--- a/tests/os.js
+++ b/tests/os.js
@@ -23,6 +23,7 @@ test('it should windows correctly from filename', ()=> {
   assert.deepEqual('win32', os.guessFromFilename('particl-desktop-2.3.6-win-ia32.zip'))
   assert.deepEqual('win32', os.guessFromFilename('Multrin-1.3.0-ia32-win.zip'))
   assert.deepEqual('win32', os.guessFromFilename('Multrin-1.3.0-ia32-win.exe'))
+  assert.deepEqual('win32', os.guessFromFilename('Assessment.Disaggregation-1.1.4.Setup.exe'))
 });
 
 test('it should guess correctly from file list', ()=> {