Paket.bootstrapper.exe unable to communicate with GitHub (5.138.5)

Description

GitHub shut down an old insecure encryption cypher, and paket.bootstrapper.exe is not able to talk to their servers. More info here: https://githubengineering.com/crypto-removal-notice/

Repro steps

Please provide the steps required to reproduce the problem

1. Download latest paket.bootstrapper.exe

2. Try to run it. Observe error.

Checking Paket version (downloading latest stable)...
The request was aborted: Could not create SSL/TLS secure channel. (Github - cached)

Expected behavior

The bootstrapper downloads the latest version of paket.exe.

Actual behavior

Checking Paket version (downloading latest stable)...
The request was aborted: Could not create SSL/TLS secure channel. (Github - cached)

Known workarounds

None.

[ptrstpp950]

Workaround Add registry keys to force NET framework to use strong encryption. For example PowerShell commands:

new-itemproperty -path "HKLM:\SOFTWARE\Microsoft\.NETFramework\v4.0.30319" -name "SchUseStrongCrypto" -Value 1 -PropertyType "DWord";
new-itemproperty -path "HKLM:\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v4.0.30319" -name "SchUseStrongCrypto" -Value 1 -PropertyType "DWord"

[csmager]

I’ve updated to the bootstrapper in the 5.141.0 release (with the fix from #3066), I now get a different error in ‘magic mode’:

The request was aborted: The connection was closed unexpectedly. (Github - cached (temporarily ignore updates))

In normal mode, I see this:

Checking Paket version (downloading latest stable)… Hash file of version 5.141.0 not found in cache. Starting download from https://github.com/fsprojects/Paket/releases/download/5.141.0/paket-sha256.txt ‘Github - cached’ download failed. If using Mono, you may need to import trusted certificates using the ‘mozroots’ tool as none are contained by default. Trying fallback download from ‘Nuget - cached’.