diff --git a/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/StringResult.kt b/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/StringResult.kt
index 14e8c5a..4809123 100644
--- a/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/StringResult.kt
+++ b/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/StringResult.kt
@@ -11,11 +11,11 @@ class StringResult internal constructor(private val stringResultT: LibJna.String
         return libJna.get_string_err(stringResultT) != null
     }
     
-    fun err(): String? {
+    fun err(): Error? {
         val errPointer = libJna.get_string_err(stringResultT)
         val err = errPointer?.getString(0)
         libJna.free_string(errPointer)
-        return err
+        return err?.let { Error.valueOf(it) }
     }
     
     fun ok(): String? {
diff --git a/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/VoidResult.kt b/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/VoidResult.kt
index 50b1c86..dd42517 100644
--- a/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/VoidResult.kt
+++ b/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/VoidResult.kt
@@ -11,11 +11,11 @@ class VoidResult internal constructor(private val voidResultT: LibJna.VoidResult
         return libJna.get_void_err(voidResultT) != null
     }
     
-    fun err(): String? {
+    fun err(): Error? {
         val errPointer = libJna.get_void_err(voidResultT)
         val err = errPointer?.getString(0)
         libJna.free_string(errPointer)
-        return err
+        return err?.let { Error.valueOf(it) }
     }
     
     protected fun finalize() {
diff --git a/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/WalletResult.kt b/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/WalletResult.kt
index 2ac325d..1f882d1 100644
--- a/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/WalletResult.kt
+++ b/bdk-kotlin/jvm/src/main/java/org/bitcoindevkit/bdk/WalletResult.kt
@@ -16,11 +16,11 @@ class WalletResult(
         return libJna.get_wallet_err(walletResultT) != null
     }
 
-    fun err(): String? {
+    fun err(): Error? {
         val errPointer = libJna.get_wallet_err(walletResultT)
         val err = errPointer?.getString(0)
         libJna.free_string(errPointer)
-        return err
+        return err?.let { Error.valueOf(it) }
     }
 
     fun ok(): Wallet? {
diff --git a/bdk-kotlin/test-fixtures/src/main/java/org/bitcoindevkit/bdk/LibTest.kt b/bdk-kotlin/test-fixtures/src/main/java/org/bitcoindevkit/bdk/LibTest.kt
index 49e6d85..2628607 100644
--- a/bdk-kotlin/test-fixtures/src/main/java/org/bitcoindevkit/bdk/LibTest.kt
+++ b/bdk-kotlin/test-fixtures/src/main/java/org/bitcoindevkit/bdk/LibTest.kt
@@ -26,7 +26,7 @@ abstract class LibTest : LibBase() {
         val walletErr = badWalletResult.err()
         assertNotNull(walletErr)
         log.debug("wallet error $walletErr")
-        assertEquals("Descriptor", walletErr)
+        assertEquals(Error.Descriptor, walletErr)
         val wallet = badWalletResult.ok()
         assertNull(wallet)
     }