Recently, one of my clients encountered an issue while trying to install SQL Server 2014. They received an error message stating “Unable to Initialize SSL Support. The client and server cannot communicate, because they do not possess a common algorithm.” This error can cause SQL startup failures and prevent the installation process from completing successfully.
Upon further investigation, I found that the error was related to the server’s inability to load the necessary certificate for initiating an SSL connection. The error code associated with this issue was 0x80090331. The SQL Server ERRORLOG provided additional information, including error numbers and hex codes, which helped in identifying the problem.
The root cause of this error is the lack of support for TLS 1.2 in the version of SQL Server being installed. To resolve this issue, the following steps can be taken:
- Disable TLS 1.2 and enable TLS 1.0 and TLS 1.1 on the server.
- Reboot the server.
- If the error occurred during installation, uninstall SQL Server.
- Reinstall SQL Server, ensuring that TLS 1.2 is disabled.
- Apply the necessary patch to support TLS 1.2 (refer to the provided link).
- Enable TLS 1.2 again and disable TLS 1.0 and TLS 1.1.
- Reboot the server once again.
- Test connectivity to the SQL Server to ensure that the issue has been resolved.
It is important to note that the above steps involve modifying the Windows registry. Here is an example of the registry key for TLS 1.0:
Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0] [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Client] "Enabled"=dword:ffffffff "DisabledByDefault"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Server] "Enabled"=dword:ffffffff "DisabledByDefault"=dword:00000000
These registry keys and values can also be applied to other TLS versions, such as TLS 1.1 and TLS 1.2.
I hope this solution helps anyone who encounters this error during the SQL Server installation process. If you have any other options or solutions, please feel free to comment and share your insights.