diff --git a/basepath.go b/basepath.go
index 2e72793..faa1012 100644
--- a/basepath.go
+++ b/basepath.go
@@ -51,7 +51,7 @@ func NewBasePathFs(source Fs, path string) Fs {
 // on a file outside the base path it returns the given file name and an error,
 // else the given file with the base path prepended
 func (b *BasePathFs) RealPath(name string) (path string, err error) {
-	if err := validateBasePathName(name); err != nil {
+	if err := validateBasePathName(name, b.path); err != nil {
 		return name, err
 	}
 
@@ -64,7 +64,7 @@ func (b *BasePathFs) RealPath(name string) (path string, err error) {
 	return path, nil
 }
 
-func validateBasePathName(name string) error {
+func validateBasePathName(name string, base string) error {
 	if runtime.GOOS != "windows" {
 		// Not much to do here;
 		// the virtual file paths all look absolute on *nix.
@@ -73,7 +73,7 @@ func validateBasePathName(name string) error {
 
 	// On Windows a common mistake would be to provide an absolute OS path
 	// We could strip out the base part, but that would not be very portable.
-	if filepath.IsAbs(name) {
+	if filepath.IsAbs(name) && base != "" {
 		return os.ErrNotExist
 	}