Azure text-to-speech API is not accessable on Windows8, 8.1, Server2012, Server2012R2

Copper Contributor



I found that Azure TTS Service API did not work on Windows 8,  8.1, Server2012, Server2012R2 since 2022-01.


It has worked well until 2021-11 at least .


Other Azure APIs like authentication, speech recognition API works and only Azure TTS Service API does not work on Windows 8/8.1/Server2012/Server2012R2.

I confirmed that TLS 1.2 was used for all SSL communication on Windows 8.1 using WireShark but TLS 1.2 Handshake Failure error occurred like the followings;

TLSv1.2 Record Layer: Handshake Protocol: Client Hello
TLSv1.2 Record Layer: Alert (Level: Fatal, Description: Handshake Failure).



I spent a lot of time for TLS handshaking issue of Azure TTS Service API and found the actual reason.

It was TLS cipher suite issue of Azure TTS Service API Server.


I executed sslscan to and the result was as the following;
Preferred TLSv1.2 128 bits ECDHE-RSA-AES128-GCM-SHA256 Curve 25519 DHE 253
Accepted TLSv1.2 256 bits ECDHE-RSA-AES256-GCM-SHA384 Curve 25519 DHE 253
Accepted TLSv1.2 256 bits ECDHE-RSA-CHACHA20-POLY1305 Curve 25519 DHE 253

I compared packet capturing result of WireShark between Windows 8.1 and Windows 10.


The result of Windows 10 has ECDHE-RSA-AES128-GCM-SHA256 and ECDHE-RSA-AES256-GCM-SHA384 but the result of Windows 8.1 does not.

So, Azure TTS API cannot work on Windows8/8.1/Server2012/Server2012R2 and there is no way to solve or workaround in client side.

I think that it must be solved at azure server side.


I found a same issue at the following link;

Best regards.

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