How to cope with "A potentially dangerous Request.Path value was detected from the client" error in web client

Question: While I am connected to my infobase via web client, I occasionally get an error message “A potentially dangerous Request.Path value was detected from the client". What does that mean and how to cope with it?   

Answer: This message indicates that an error occurred but for security reasons the system does not tell you what actually has happened. Below is the error message.

In order for the system to show the actual error report, you should modify the web.config file. Locate the file in the C:\inetpub\wwwroot\<published infobase> folder and open it with a text editor of your choice. By default, the file contents look like this:

Edit the file as seen on the screenshot below:

Alternative Methods

This error can also occur for users deploying a 1C:Enterprise web server via Internet Information Services (IIS) on Windows. It is typically caused by incorrect configuration of the application pool or site properties after installing IIS. This issue arises when unsafe URL characters, like (:), are detected, preventing proper request handling. Below are two step-by-step methods to resolve the issue.

Method I: Reconfigure “ISAPI-dll”

• Open Internet Information Services (IIS) Manager.
• Navigate to [Server Name] > Sites > Default Web Site and select the appropriate site.
• In the IIS section, click on Handler Mappings.
• Locate ISAPI-dll in the list.
• Configure its properties as follows:
  • Request Path: *.dll
  • Module: IsapiModule
  • Executable: C:\Program Files or Program Files (x86)\1cv8\[1C:Enterprise version]\bin\wsisapi.dll
    
    

Method II: Change managed pipeline mode

• Locate DefaultAppPool under [Server Name] > Application Pools.
• Double-click on DefaultAppPool and set Managed Pipeline Mode to Classic.;
  
  

After making these corrections, it is recommended to publish the web server on 1C:Enterprise again.