diff --git a/Aaru.Archives/Symbian/Files.cs b/Aaru.Archives/Symbian/Files.cs
index 675e1be2e..0057f9005 100644
--- a/Aaru.Archives/Symbian/Files.cs
+++ b/Aaru.Archives/Symbian/Files.cs
@@ -67,5 +67,17 @@ public sealed partial class Symbian
                                          : x.destinationName.Equals(fileName, StringComparison.CurrentCulture));
     }
 
+    /// <inheritdoc />
+    public long GetCompressedSize(int entryNumber)
+    {
+        if(!_opened)
+            return -1;
+
+        if(entryNumber < 0 || entryNumber >= _files.Count)
+            return -1;
+
+        return _files[entryNumber].length;
+    }
+
 #endregion
 }
\ No newline at end of file
diff --git a/Aaru.Archives/Symbian/Unsupported.cs b/Aaru.Archives/Symbian/Unsupported.cs
index b0f829981..29a090964 100644
--- a/Aaru.Archives/Symbian/Unsupported.cs
+++ b/Aaru.Archives/Symbian/Unsupported.cs
@@ -45,9 +45,6 @@ public sealed partial class Symbian
 {
 #region IArchive Members
 
-    /// <inheritdoc />
-    public long GetCompressedSize(int entryNumber) => throw new NotImplementedException();
-
     /// <inheritdoc />
     public long GetUncompressedSize(int entryNumber) => throw new NotImplementedException();