ERROR: -73 Unable to Listen on TCP Port 443 SSL Could Not Load TLS DLLs [Could n

[rjolda]

Hi All,
I am running a SSL server on a Virtual Machine.   
I upgraded from NT10 to NT 11.
NT works OK on my desktop but on my remote Virtual Machine I get the ERROR:
ERROR: -73 Unable to Listen on TCP Port 443 SSL Could Not Load TLS DLLs [Could not load the TLS DLLs - libssl-1_1.dll, libcrypto-1_1.dll, msvcr120.dll]
I have updated the files - however, I get an ERROR on installing Visual Studio 2017 on my remote VM.  This is probably the cause for the above error message. 
QUESTION:  Can I install other required files on my VM or does the Visual Studio 2017 intertwine with the OS (Windows Server 2012 R2)
TIA,
Ron Jolda

[Bruce]

Hi Ron,
as per the docs, you need to install the Visual Studio 2017 redistributable on the machine.
http://www.capesoft.com/docs/NetTalk11/NetTalk.htm#DeployingAtlsClientOrServer

Cheers
Bruce

[Vinnie]

Hi no problem using VM ware
But I did need  to install vc-redist.x86.exe on the windows guest.
No change required to the host machine.
Cheers
Vinnie

[rjolda]

Hi,
I had to run a bunch of updates and Visual Studio specifically requested update KB2919355 had to be installed AFTER I had done all the routine updates.  After I installed KB2919355 and re-booted, I was able to Get a successful Visual Studio 2017 and now SSL app working fine!
Ron

[Carlos Gutierrez]

FWIW, I had lots of support request with this error, and sometimes installing both "Visual Studio 2017 (x86) runtime" and "Update for Universal C Runtime" didn't fix the problem.

Then I found this alternate build of the OpenSSL binares, part of a free Delphi library, that don't have dependencies on VC runtime. After distributing these dlls instead, we haven't seen the error again.

http://wiki.overbyte.eu/wiki/index.php/ICS_Download#Download_OpenSSL_Binaries_.28required_for_SSL-enabled_components.29