diff --git a/de4dot.code/deobfuscators/CryptoObfuscator/StringDecrypter.cs b/de4dot.code/deobfuscators/CryptoObfuscator/StringDecrypter.cs
index f8b2b7ed..599f076c 100644
--- a/de4dot.code/deobfuscators/CryptoObfuscator/StringDecrypter.cs
+++ b/de4dot.code/deobfuscators/CryptoObfuscator/StringDecrypter.cs
@@ -121,6 +121,8 @@ namespace de4dot.code.deobfuscators.CryptoObfuscator {
 					continue;
 				if (type.Methods.Count != 3)
 					continue;
+				if (type.NestedTypes.Count > 0)
+					continue;
 
 				MethodDefinition method = null;
 				foreach (var m in type.Methods) {