diff --git a/src/ecpair.js b/src/ecpair.js
index d81b5be..c647196 100644
--- a/src/ecpair.js
+++ b/src/ecpair.js
@@ -66,6 +66,8 @@ ECPair.fromWIF = function (string, network) {
     network = network.filter(function (network) {
       return version === network.wif
     }).pop()
+
+    if (!network) throw new Error('Unknown network version')
   }
 
   network = network || NETWORKS.bitcoin
diff --git a/src/hdnode.js b/src/hdnode.js
index 0efd61c..27228e9 100644
--- a/src/hdnode.js
+++ b/src/hdnode.js
@@ -66,7 +66,7 @@ HDNode.fromBase58 = function (string, networks) {
              version === network.bip32.public
     }).pop()
 
-    if (!network) throw new Error('Invalid network version')
+    if (!network) throw new Error('Unknown network version')
 
   // otherwise, assume a network object (or default to bitcoin)
   } else {
diff --git a/test/fixtures/ecpair.json b/test/fixtures/ecpair.json
index d4e8cfb..6f0a1a2 100644
--- a/test/fixtures/ecpair.json
+++ b/test/fixtures/ecpair.json
@@ -111,7 +111,7 @@
         "WIF": "92Qba5hnyWSn5Ffcka56yMQauaWY6ZLd91Vzxbi4a9CCetaHtYj"
       },
       {
-        "exception": "Invalid network version",
+        "exception": "Unknown network version",
         "WIF": "brQnSed3Fia1w9VcbbS6ZGDgJ6ENkgwuQY2LS7pEC5bKHD1fMF"
       },
       {
diff --git a/test/fixtures/hdnode.json b/test/fixtures/hdnode.json
index 59e0647..877dd6d 100644
--- a/test/fixtures/hdnode.json
+++ b/test/fixtures/hdnode.json
@@ -199,7 +199,7 @@
         "string": "xprvQQQQQQQQQQQQQQQQCviVfJSKyQ1mDYahRjijr5idH2WwLsEd4Hsb2Tyh8RfQMuPh7f7RtyzTtdrbdqqsunu5Mm3wDvUAKRHSC34sJ7in334"
       },
       {
-        "exception": "Invalid network version",
+        "exception": "Unknown network version",
         "string": "1111111111111adADjFaSNPxwXqLjHLj4mBfYxuewDPbw9hEj1uaXCzMxRPXDFF3cUoezTFYom4sEmEVSQmENPPR315cFk9YUFVek73wE9"
       },
       {