diff --git a/README.md b/README.md
index 363d282..f6a0584 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# S3
+[utils_test.go](..%2Foss%2Futils_test.go)# S3
 
 A s3 disk driver for `facades.Storage()` of Goravel.
 
diff --git a/s3_test.go b/s3_test.go
index fe349f9..e44831b 100644
--- a/s3_test.go
+++ b/s3_test.go
@@ -269,6 +269,7 @@ func TestStorage(t *testing.T) {
 			name: "Put",
 			setup: func() {
 				assert.Nil(t, driver.Put("Put/1.txt", "Goravel"))
+				assert.True(t, driver.Exists("Put"))
 				assert.True(t, driver.Exists("Put/1.txt"))
 				assert.True(t, driver.Missing("Put/2.txt"))
 				assert.Nil(t, driver.DeleteDirectory("Put"))
@@ -290,6 +291,7 @@ func TestStorage(t *testing.T) {
 				fileInfo := &File{path: "test.txt"}
 				path, err := driver.PutFile("PutFile", fileInfo)
 				assert.Nil(t, err)
+				assert.True(t, driver.Exists("PutFile"))
 				assert.True(t, driver.Exists(path))
 				data, err := driver.Get(path)
 				assert.Nil(t, err)
diff --git a/utils.go b/utils.go
index 7d21262..8c9712e 100644
--- a/utils.go
+++ b/utils.go
@@ -1,8 +1,8 @@
 package s3
 
 import (
+	"fmt"
 	"path"
-	"path/filepath"
 	"strings"
 
 	"github.com/goravel/framework/contracts/filesystem"
@@ -18,18 +18,18 @@ func fullPathOfFile(filePath string, source filesystem.File, name string) (strin
 			return "", err
 		}
 
-		return filepath.Join(filePath, strings.TrimSuffix(strings.TrimPrefix(path.Base(name), string(filepath.Separator)), string(filepath.Separator))+"."+extension), nil
+		return fmt.Sprintf("%s/%s.%s", filePath, strings.TrimSuffix(strings.TrimPrefix(path.Base(name), "/"), "/"), extension), nil
 	} else {
-		return filepath.Join(filePath, strings.TrimPrefix(path.Base(name), string(filepath.Separator))), nil
+		return fmt.Sprintf("%s/%s", filePath, strings.TrimPrefix(path.Base(name), "/")), nil
 	}
 }
 
 func validPath(path string) string {
-	realPath := strings.TrimPrefix(path, "."+string(filepath.Separator))
-	realPath = strings.TrimPrefix(realPath, string(filepath.Separator))
+	realPath := strings.TrimPrefix(path, "./")
+	realPath = strings.TrimPrefix(realPath, "/")
 	realPath = strings.TrimPrefix(realPath, ".")
-	if realPath != "" && !strings.HasSuffix(realPath, string(filepath.Separator)) {
-		realPath += string(filepath.Separator)
+	if realPath != "" && !strings.HasSuffix(realPath, "/") {
+		realPath += "/"
 	}
 
 	return realPath
diff --git a/utils_test.go b/utils_test.go
new file mode 100644
index 0000000..ee35efd
--- /dev/null
+++ b/utils_test.go
@@ -0,0 +1,29 @@
+package s3
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFullPathOfFile(t *testing.T) {
+	path, err := fullPathOfFile("a/b", &File{path: "logo.png"}, "c")
+	assert.Equal(t, "a/b/c.png", path)
+	assert.Nil(t, err)
+
+	path, err = fullPathOfFile("a/b", &File{path: "logo.png"}, "c.jpg")
+	assert.Equal(t, "a/b/c.jpg", path)
+	assert.Nil(t, err)
+}
+
+func TestValidPath(t *testing.T) {
+	assert.Equal(t, "a/", validPath("./a"))
+	assert.Equal(t, "a/", validPath(".a"))
+	assert.Equal(t, "a/", validPath("/a"))
+	assert.Equal(t, "a/", validPath("./a/"))
+	assert.Equal(t, "a/", validPath(".a/"))
+	assert.Equal(t, "a/", validPath("/a/"))
+	assert.Equal(t, "", validPath("./"))
+	assert.Equal(t, "", validPath("."))
+	assert.Equal(t, "", validPath("/"))
+}