diff --git a/ArcFormats/ArcMiris.cs b/ArcFormats/ArcMiris.cs
index 50d1c9b0..e55c2b70 100644
--- a/ArcFormats/ArcMiris.cs
+++ b/ArcFormats/ArcMiris.cs
@@ -51,7 +51,7 @@ namespace GameRes.Formats.Miris
 
         public override ArcFile TryOpen (ArcView file)
         {
-            var base_dir = Path.GetDirectoryName (file.Name);
+            var base_dir = VFS.GetDirectoryName (file.Name);
             var base_name = Path.GetFileNameWithoutExtension (file.Name);
             var list_file = VFS.CombinePath (base_dir, base_name+"l.dat");
             if (!VFS.FileExists (list_file))
diff --git a/ArcFormats/Cmvs/ImagePB3.cs b/ArcFormats/Cmvs/ImagePB3.cs
index 5be56d14..eb5e2aff 100644
--- a/ArcFormats/Cmvs/ImagePB3.cs
+++ b/ArcFormats/Cmvs/ImagePB3.cs
@@ -296,7 +296,7 @@ namespace GameRes.Formats.Purple
             // judging by the code, files with "pb3" extension could as well contain PNG or BMP images,
             // so we couldn't just shortcut to another instance of Pb3Reader here.
 
-            var path = Path.GetDirectoryName (m_info.FileName);
+            var path = VFS.GetDirectoryName (m_info.FileName);
             name = VFS.CombinePath (path, name);
             if (name.Equals (m_info.FileName, StringComparison.InvariantCultureIgnoreCase))
                 throw new InvalidFormatException();
diff --git a/ArcFormats/Entis/ImageERI.cs b/ArcFormats/Entis/ImageERI.cs
index 6c5570ea..7dbde246 100644
--- a/ArcFormats/Entis/ImageERI.cs
+++ b/ArcFormats/Entis/ImageERI.cs
@@ -297,7 +297,7 @@ namespace GameRes.Formats.Entis
                         if ((meta.BPP + 7) / 8 < 3)
                             throw new InvalidFormatException();
 
-                        ref_file = VFS.CombinePath (Path.GetDirectoryName (meta.FileName), ref_file);
+                        ref_file = VFS.CombinePath (VFS.GetDirectoryName (meta.FileName), ref_file);
                         using (var ref_src = VFS.OpenSeekableStream (ref_file))
                         {
                             var ref_info = ReadMetaData (ref_src) as EriMetaData;
diff --git a/ArcFormats/Glib2/ImagePGX.cs b/ArcFormats/Glib2/ImagePGX.cs
index 48cba5b2..88d4df92 100644
--- a/ArcFormats/Glib2/ImagePGX.cs
+++ b/ArcFormats/Glib2/ImagePGX.cs
@@ -151,7 +151,7 @@ namespace GameRes.Formats.Glib2
         {
             try
             {
-                var info_name = VFS.CombinePath (Path.GetDirectoryName (image_name), "info");
+                var info_name = VFS.CombinePath (VFS.GetDirectoryName (image_name), "info");
                 if (!VFS.FileExists (info_name))
                     return null;
                 if (string.IsNullOrEmpty (m_last_info_dir)
diff --git a/ArcFormats/Majiro/ImageRCT.cs b/ArcFormats/Majiro/ImageRCT.cs
index 3f36e8d3..7dff2ad0 100644
--- a/ArcFormats/Majiro/ImageRCT.cs
+++ b/ArcFormats/Majiro/ImageRCT.cs
@@ -182,7 +182,7 @@ namespace GameRes.Formats.Majiro
             try
             {
                 string name = Encodings.cp932.GetString (name_bin, 0, name_bin.Length-1);
-                string dir_name = Path.GetDirectoryName (meta.FileName);
+                string dir_name = VFS.GetDirectoryName (meta.FileName);
                 name = VFS.CombinePath (dir_name, name);
                 if (VFS.FileExists (name))
                 {