diff --git a/DigitalData.Core.Security/AsymCryptService.cs b/DigitalData.Core.Security/AsymCryptService.cs
index c6ff3cf..cc471af 100644
--- a/DigitalData.Core.Security/AsymCryptService.cs
+++ b/DigitalData.Core.Security/AsymCryptService.cs
@@ -12,6 +12,20 @@ namespace DigitalData.Core.Security
     {
         public IEnumerable<IRSADecryptor> Decryptors => _params.Decryptors;
 
+        public IRSADecryptor this[string key]
+        {
+            get
+            {
+                var key_params = key.Split(_params.KeyNameSeparator);
+
+                if (key_params.Length != 2)
+                    throw new ArgumentException($"Invalid key format. Expected two segments separated by '{_params.KeyNameSeparator}', but received: '{key}'.", nameof(key));
+
+                return _params.Decryptors.FirstOrDefault(d => d.Issuer == key_params[0] && d.Audience == key_params[1])
+                    ?? throw new KeyNotFoundException($"No decryptor found matching the issuer '{key_params[0]}' and audience '{key_params[1]}'.");
+            }
+        }
+
         public AsymCryptService(IOptions<TAsymCryptParams> options, ILogger<AsymCryptService<TAsymCryptParams>>? logger = null) : base(options)
         {
             logger?.LogInformation("Core.Secrets version: {Version}, Created on: {CreationDate}.", Secrets.Version, Secrets.CreationDate.ToString("dd.MM.yyyy"));
diff --git a/DigitalData.Core.Security/Config/AsymCryptParams.cs b/DigitalData.Core.Security/Config/AsymCryptParams.cs
index c6cc565..2108183 100644
--- a/DigitalData.Core.Security/Config/AsymCryptParams.cs
+++ b/DigitalData.Core.Security/Config/AsymCryptParams.cs
@@ -53,7 +53,7 @@ namespace DigitalData.Core.Security.Config
                     if (decryptor.IsEncrypted)
                         file_name_params.Add(Secrets.Version);
 
-                    var path = Path.Combine(PemDirectory, string.Join(Separator, file_name_params));
+                    var path = Path.Combine(PemDirectory, string.Join(FileNameSeparator, file_name_params));
 
                     if (File.Exists(path))
                         decryptor.SetPem(File.ReadAllText(path));