Use PowerShell to Disable Weak Encryption

This article helps you disable certain protocols to pass payment card industry
(PCI) compliance scans by using Windows® PowerShell®.

The following script block includes elements that disable weak
encryption mechanisms by using registry edits. See the script block comments for details. After you run any element of the
script you need to reboot the Windows server to fully apply the changes.

# Make Transport Layer Security (TLS) 1.2 protocol registry keys
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client"

# Enable TLS 1.2 for client and server SCHANNEL communications

new-itemproperty -path     "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server" -name "Enabled" -value 1 -PropertyType "DWord"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server" -name "DisabledByDefault" -value 0 -PropertyType "DWord"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client" -name "Enabled" -value 1 -PropertyType "DWord"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client" -name "DisabledByDefault" -value 0 -PropertyType "DWord"

# Make and enable TLS 1.1 for client and server SCHANNEL communications

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Client"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server" -name "Enabled" -value 1 -PropertyType "DWord"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server" -name "DisabledByDefault" -value 0 -PropertyType "DWord"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Client" -name "Enabled" -value 1 -PropertyType "DWord"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Client" -name "DisabledByDefault" -value 0 -PropertyType "DWord"

# Disable Secure Sockets Layer (SSL) 2.0

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Server"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Server" -name Enabled -value 0 -PropertyType "DWord"

# Enable SSL 3.0

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server" -name Enabled -value 1 -PropertyType "DWord"

# Disable weak cyphers

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\Null"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\Null" -name "Enabled" -value 0 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\DES 56"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\DES 56/56"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\DES 56/56" -name "Enabled" -value 0 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 40"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 40/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 40/128" -name "Enabled" -value 0 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 56"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 56/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 40/128" -name "Enabled" -value 0 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 128"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 128/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 128/128" -name "Enabled" -value 0 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 40"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 40/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 40/128" -name "Enabled" -value 0 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 56"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 56/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 56/128" -name "Enabled" -value 0 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 64"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 64/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 64/128" -name "Enabled" -value 0 -PropertyType "Dword"

# Enable strong cyphers

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 128"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 128/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 128/128" -name "Enabled" -value 1 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\Triple DES 168"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\Triple DES 168/168"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\Triple DES 168/168" -name "Enabled" -value 1 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\AES 128"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\AES 128/128"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\AES 128/128" -name "Enabled" -value 1 -PropertyType "Dword"

md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\AES 256"
md "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\AES 256/256"
new-itemproperty -path "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\AES 256/256" -name "Enabled" -value 1 -PropertyType "Dword"