diff --git a/lib/file.js b/lib/file.js
index 707545a..1ce1c7a 100644
--- a/lib/file.js
+++ b/lib/file.js
@@ -171,18 +171,22 @@ function loadEnvFromArgs(args, callback) {
     }
 }
 
-function isAbsolutePath(path) {
+function normalizePath(path) {
     if (typeof path !== "string")
         return false;
     
-    path = path.replace(/^\s+/, "").replace(/\s+$/, "");
+    return (function(s) {
+        s = s.trim();
+        return (s.charAt(0) === "\uFEFF" ? s.slice(1) : s);
+    })(path);
+}
 
-    if (path.charAt(0) === "\uFEFF")
-        path = path.slice(1);
+function isAbsolutePath(path) {
+    var normalizedPath = normalizePath(path);
 
-    return (/^[a-zA-Z]:[\\/]/).test(path) ||
-         (/^[\\/]{2,}/).test(path) ||
-         (/^\//).test(path);
+    return (/^[a-zA-Z]:[\\/]/).test(normalizedPath) ||
+         (/^[\\/]{2,}/).test(normalizedPath) ||
+         (/^\//).test(normalizedPath);
 };
 
 exports.fileExists = fileExists;
@@ -201,6 +205,7 @@ exports.appendFile = appendFile;
 exports.rotateFile = rotateFile;
 exports.loadEnvFromFile = loadEnvFromFile;
 exports.loadEnvFromArgs = loadEnvFromArgs;
+exports.normalizePath = normalizePath;
 exports.isAbsolutePath = isAbsolutePath;
 
 exports.CdoCharset = PipeIPC.CdoCharset;
diff --git a/lib/msoffice.js b/lib/msoffice.js
index eb7c738..ca31a88 100644
--- a/lib/msoffice.js
+++ b/lib/msoffice.js
@@ -128,7 +128,7 @@ function PowerPoint() {
     this.open = function(filename) {
         if (typeof filename !== "undefined") {
             // check type of the path
-            if (filename.indexOf(":\\") < 0 && filename.indexOf(":/") < 0) {
+            if (!FILE.isAbsolutePath(filename)) {
                 filename = SYS.getCurrentWorkingDirectory() + "\\" + filename;  // get absolute path
             }
             if (FILE.fileExists(filename)) {
@@ -210,7 +210,7 @@ function Word() {
     this.open = function(filename) {
         if (typeof filename !== "undefined") {
             // check type of the path
-            if (filename.indexOf(":\\") < 0 && filename.indexOf(":/") < 0) {
+            if (!FILE.isAbsolutePath(filename)) {
                 filename = SYS.getCurrentWorkingDirectory() + "\\" + filename;  // get absolute path
             }
             if (FILE.fileExists(filename)) {