Changes to the SameSite Cookie in KB4534271 and other updates

SameSite cookie prevents cross-site request forgery (CSRF) attacks by restricting the usage of third-party resources in web applications. Resource examples are the URLs in GET, POST, link, iframe, Ajax, image etc. If a URL is different than the actual web application’s URL, it means that it’s a third-party resource.

“rzc discover exited with code -2147450749” and “hostpolicy.dll required” errors

We have recently upgrade a .NET Core 2.2 application to 3.1 version. While trying to run it in Visual Studio, we came across “rzc discover exited” and “hostpolicy.dll required” errors:

  • In Visual Studio output while trying to run the solution: rzc discover exited with code -2147450749
  • In PowerShell after performing “build run” command: A fatal error was encountered. The library 'hostpolicy.dll' required to execute the application was not found in [path]

HTTP Error 500.30 – ANCM In-Process Start Failure (Solved)

Visual Studio makes it easy to run your application project by using IIS installed in Windows. You don’t have to explicitly go to IIS Manager and deploy your application there. You can simply click the “Run” (green arrow) icon to view your project on browser.

The program can’t start because MSVCR71.dll is missing

IIS relies on libraries that contains functions to host ASP.NET, PHP or other types of web applications. If a library is missing or corrupt in the server, your application may not function properly and throw an error such as “The program can’t start because MSVCR71.dll is missing“.

(Solved) Disallowed Parent Path error (ASP 0131 ASP_LOG_ERROR)

There are two ways to reference a file in your code: Using an absolute path (Ex: /folder/file) or using a relative path (Ex: ../folder/file). If you use a relative path in your ASP code but your IIS server is not configured properly, you may come across to “Disallowed Parent Path” error (ASP 0131 ASP_LOG_ERROR).

The file has not been pre-compiled, and cannot be requested (Solved)

You may run into “The file has not been pre-compiled, and cannot be requested” error intermittently while accessing your ASP.NET application. The intermittent nature of the issue makes it hard to troubleshoot but there are a couple of common causes of this issue. Let’s have a look a them and the possible solutions.