Thanks! That helped, but I have two follow-ups. 1) To whom would I suggest minor changes to the available installation instructions to help avoid future such misunderstandings? 2) A subsequent fatal error (should this also be submitted as a new thread?): Could Not Find c:\Users\Owner\LocalPrograms\OpenSSL\openssl-1.1.1g\libcrypto-1_1-x64. *** build output *** cl /Zi /Fdossl_static.pdb /Gs0 /GF /Gy /MD /W3 /wd4090 /nologo /O2 /I "." /I "include" -D"L_ENDIAN" -D"OPENSSL_PIC" -D"OPENSSL_CPUID_OBJ" -D"OPENSSL_IA32_SSE2" -D"OPENSSL_BN_ASM_MONT" -D"OPENSSL_BN_ASM_MONT5" -D"OPENSSL_BN_ASM_GF2m" -D"SHA1_ASM" -D"SHA256_ASM" -D"SHA512_ASM" -D"KECCAK1600_ASM" -D"RC4_ASM" -D"MD5_ASM" -D"AESNI_ASM" -D"VPAES_ASM" -D"GHASH_ASM" -D"ECP_NISTZ256_ASM" -D"X25519_ASM" -D"POLY1305_ASM" -D"OPENSSLDIR=\"C:\\Program Files\\Common Files\\SSL\"" -D"ENGINESDIR=\"C:\\usr\\local\\OPENSSL\\openssl-1.1.1g\\x86_64-8.1.0-posix- seh-rt_v6-rev0\\lib\\engines-1_1\"" -D"OPENSSL_SYS_WIN32" -D"WIN32_LEAN_AND_MEAN" -D"UNICODE" -D"_UNICODE" -D"_CRT_SECURE_NO_DEPRECATE" -D"_WINSOCK_DEPRECATED_NO_WARNINGS" -D"OPENSSL_USE_APPLINK" -D"NDEBUG" /Zs /showIncludes "ms\uplink.c" 2>&1 > ms\uplink.d "C:\Perl64\bin\perl.exe" "util\mkdef.pl" crypto 32 > libcrypto.def IF EXIST .manifest DEL /F /Q .manifest IF EXIST libcrypto-1_1-x64.dll DEL /F /Q libcrypto-1_1-x64.dll link /nologo /debug /dll /nologo /debug /implib:libcrypto.lib /out:libcrypto-1_1-x64.dll /def:libcrypto.def @C:\Users\Owner\AppData\Local\Temp\nm26DC.tmp || (DEL /Q libcrypto-1_1-x64.* libcrypto.lib && EXIT 1) crypto\aes\aesni-mb-x86_64.obj : fatal error LNK1112: module machine type 'x64' conflicts with target machine type 'x86' Could Not Find c:\Users\Owner\LocalPrograms\OpenSSL\openssl-1.1.1g\libcrypto-1_1-x64.* NMAKE : fatal error U1077: 'link' : return code '0x1' Stop. NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Tools\MSVC\14.26.28801\bin\HostX86\x86\nmake.exe"' : return code '0x2' Stop. -----Original Message----- From: openssl-users <openssl-users-bounces@xxxxxxxxxxx> On Behalf Of Matt Caswell Sent: Thursday, June 25, 2020 12:15 PM To: openssl-users@xxxxxxxxxxx Subject: Re: Error building OpenSSL-1.1.1g On 25/06/2020 18:32, Michael Wojcik wrote: >> From: openssl-users [mailto:openssl-users-bounces@xxxxxxxxxxx] On Behalf Of mhkelley2017@xxxxxxxxx >> Sent: Thursday, June 25, 2020 11:54 > >> Error: 'ml64' is not recognized as an internal or external command, >> operable program or batch file. > > It's part of Visual C. The VC-WIN64A-masm configuration (Configurations/50-masm.conf) specifies it as the assembler. Note that using masm to compile OpenSSL is no longer supported by us (although it might still work). Preferred is to use the VC-WIN64A target and the nasm compiler. If you use the Developer Studio command prompt (64-bit) it should have all the environment variables set up already to find the various VS tools. Matt > >> Building with Visual Studio 2019 Community > > Maybe VS2019 Community doesn't include the assembler? I haven't looked. Or maybe it's part of some optional component? > > In VS2017 Professional, which is what I have configured at the moment on this machine, it's in .../VC/Tools/MSVC/14.16.27023/bin/HostX86/x64, thanks to VS's gratuitously complicated directory layout. > > -- > Michael Wojcik > Distinguished Engineer, Micro Focus > > >