diff --git a/src/NpoiExtension.cs b/src/NpoiExtension.cs
index 7d4acdd..5e0a29b 100644
--- a/src/NpoiExtension.cs
+++ b/src/NpoiExtension.cs
@@ -291,7 +291,7 @@ private static IWorkbook InitializeWorkbook(string excelFile)
             var setting = Excel.Setting;
             if (setting.UserXlsx)
             {
-                if (!string.IsNullOrEmpty(excelFile) || File.Exists(excelFile))
+                if (!string.IsNullOrEmpty(excelFile) && File.Exists(excelFile))
                 {
                     using (var file = new FileStream(excelFile, FileMode.Open, FileAccess.Read))
                     {
@@ -305,7 +305,7 @@ private static IWorkbook InitializeWorkbook(string excelFile)
             }
             else
             {
-                if (!string.IsNullOrEmpty(excelFile) || File.Exists(excelFile))
+                if (!string.IsNullOrEmpty(excelFile) && File.Exists(excelFile))
                 {
                     using (var file = new FileStream(excelFile, FileMode.Open, FileAccess.Read))
                     {
diff --git a/src/Properties/AssemblyInfo.cs b/src/Properties/AssemblyInfo.cs
index a967ed5..86975a3 100644
--- a/src/Properties/AssemblyInfo.cs
+++ b/src/Properties/AssemblyInfo.cs
@@ -32,5 +32,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.4.0.0")]
-[assembly: AssemblyFileVersion("1.4.0.0")]
+[assembly: AssemblyVersion("1.4.1.0")]
+[assembly: AssemblyFileVersion("1.4.1.0")]