diff --git a/build_msvc/libsecp256k1/libsecp256k1.vcxproj b/build_msvc/libsecp256k1/libsecp256k1.vcxproj
index 0b90f341a7b..585c28e503b 100644
--- a/build_msvc/libsecp256k1/libsecp256k1.vcxproj
+++ b/build_msvc/libsecp256k1/libsecp256k1.vcxproj
@@ -15,6 +15,7 @@
   <ItemDefinitionGroup>
     <ClCompile>
       <PreprocessorDefinitions>ENABLE_MODULE_RECOVERY;ENABLE_MODULE_EXTRAKEYS;ENABLE_MODULE_SCHNORRSIG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <UndefinePreprocessorDefinitions>USE_ASM_X86_64;%(UndefinePreprocessorDefinitions)</UndefinePreprocessorDefinitions>
       <AdditionalIncludeDirectories>..\..\src\secp256k1;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>4146;4244;4267;4334</DisableSpecificWarnings>
     </ClCompile>
diff --git a/build_msvc/libsecp256k1_config.h b/build_msvc/libsecp256k1_config.h
deleted file mode 100644
index 2b1a980e273..00000000000
--- a/build_msvc/libsecp256k1_config.h
+++ /dev/null
@@ -1,15 +0,0 @@
-/**********************************************************************
- * Copyright (c) 2013, 2014 Pieter Wuille                             *
- * Distributed under the MIT software license, see the accompanying   *
- * file COPYING or http://www.opensource.org/licenses/mit-license.php.*
- **********************************************************************/
-
-#ifndef BITCOIN_LIBSECP256K1_CONFIG_H
-#define BITCOIN_LIBSECP256K1_CONFIG_H
-
-#undef USE_ASM_X86_64
-
-#define ECMULT_GEN_PREC_BITS 4
-#define ECMULT_WINDOW_SIZE 15
-
-#endif // BITCOIN_LIBSECP256K1_CONFIG_H
diff --git a/build_msvc/msvc-autogen.py b/build_msvc/msvc-autogen.py
index e02e3abdfa1..9484f0cb897 100755
--- a/build_msvc/msvc-autogen.py
+++ b/build_msvc/msvc-autogen.py
@@ -111,7 +111,6 @@ def main():
         set_properties(vcxproj_filename, '@SOURCE_FILES@\n', content)
     parse_config_into_btc_config()
     copyfile(os.path.join(SOURCE_DIR,'../build_msvc/bitcoin_config.h'), os.path.join(SOURCE_DIR, 'config/bitcoin-config.h'))
-    copyfile(os.path.join(SOURCE_DIR,'../build_msvc/libsecp256k1_config.h'), os.path.join(SOURCE_DIR, 'secp256k1/src/libsecp256k1-config.h'))
 
 if __name__ == '__main__':
     main()