62878: Acronis Cyber Files Cloud: Client errors out with "Failed to receive handshake, SSL/TLS connection failed"

use Google Translate

Operating Systems: 

Last update: 30-08-2019


On a Windows 7 machine, Acronis Cyber Files Cloud fails to establish connection, with the following error:

RequestError: (35, 'schannel: failed to receive handshake, SSL/TLS connection failed') 


This issue is related to disabling TLS 1.0 protocol due to security concerns during deployment of Acronis Cyber Cloud 7.9. Since TLS 1.0 was disabled but TLS 1.2 was not enabled by default on Windows 7, the machine cannot connect to datacenter.


Enable TLS 1.2 protocol on Windows 7 machine:

1) Open Windows Registry (Start -> Run -> regedit)

2) Create the following registry keys:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client] 

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server] 

More information

Starting with January 2020, Microsoft, Apple, Google and Mozilla are planning to disable TLS1.1 by default. While Acronis Cyber Files Cloud supports connections over TLS1.1, we recommend to enable TLS1.2 right away, as described in the Solution section.

If you still need to enable TLS1.1, create the following registry keys.
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Client] 
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server] 

See also How to restrict the use of certain cryptographic algorithms and protocols in Schannel.dll on MS Support site