Skip to main content

The request was aborted: could not create SSL/TLS secure channel–Part 1

A colleague asked for help with the following problem:

He has an ASP.NET MVC website that talks to an ASP.NET Web API backend. On development everything works as expected but on the acceptance environment, he suddenly start to get TLS errors when the httpclient invokes a call to the backend:

The request was aborted: Could not create SSL/TLS secure channel.

sslerror

Let’s take you through the journey that brought us to our final solution.

Part 1 – The unexpected .NET Framework update.

What we find especially strange was that it worked before, and that the errors only started to appear recently. This brought us on the path of what was recently changed. One of the things that happened was an upgrade to .NET Framework 4.6. Could it be?

In the .NET documentation we found that in .NET 4.6 the HttpClient defaults to TLS 1.2. Maybe that caused the error?

We updated our code to force the system to use TLS 1.0:

This worked but now we were using an older(less secure) TLS version. Let’s continue the investigation in another post…

Popular posts from this blog

DevToys–A swiss army knife for developers

As a developer there are a lot of small tasks you need to do as part of your coding, debugging and testing activities.  DevToys is an offline windows app that tries to help you with these tasks. Instead of using different websites you get a fully offline experience offering help for a large list of tasks. Many tools are available. Here is the current list: Converters JSON <> YAML Timestamp Number Base Cron Parser Encoders / Decoders HTML URL Base64 Text & Image GZip JWT Decoder Formatters JSON SQL XML Generators Hash (MD5, SHA1, SHA256, SHA512) UUID 1 and 4 Lorem Ipsum Checksum Text Escape / Unescape Inspector & Case Converter Regex Tester Text Comparer XML Validator Markdown Preview Graphic Color B

Help! I accidently enabled HSTS–on localhost

I ran into an issue after accidently enabling HSTS for a website on localhost. This was not an issue for the original website that was running in IIS and had a certificate configured. But when I tried to run an Angular app a little bit later on http://localhost:4200 the browser redirected me immediately to https://localhost . Whoops! That was not what I wanted in this case. To fix it, you need to go the network settings of your browser, there are available at: chrome://net-internals/#hsts edge://net-internals/#hsts brave://net-internals/#hsts Enter ‘localhost’ in the domain textbox under the Delete domain security policies section and hit Delete . That should do the trick…

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.