ASP.NET Web Forms License Validation Issues Without httpRuntime Configuration
Root Cause:
Web Forms applications with missing or incomplete httpRuntime configuration in web.config default to .NET Framework 4.0 TLS behavior, using TLS 1.0 instead of TLS 1.2. Our licensing servers require TLS 1.2+ for security, causing license validation HTTP requests to fail.
Customer Impact:
- License validation fails
- HTTP requests to licensing server are rejected due to unsupported TLS version
Solution:
Case 1:
Missing httpRuntime element entirely Add the complete element to <system.web> section:
<system.web>
<httpRuntime targetFramework="4.7.2" />
<!-- other system.web elements -->
</system.web>
Case 2:
httpRuntime exists but missing targetFramework Add targetFramework attribute to existing element:
<system.web>
<httpRuntime maxRequestLength="4096" executionTimeout="110" targetFramework="4.7.2" />
</system.web>
Framework Version Selection:
Use targetFramework="4.7.2" or greater for optimal compatibility
This version provides full TLS 1.2 support and modern security protocols
Alternative minimum: "4.6.1" or higher for TLS 1.2 support
Technical Details:
The compilation targetFramework alone is insufficient - httpRuntime targetFramework specifically controls TLS protocol selection during HTTP requests. Without this configuration, applications use legacy TLS 1.0 regardless of the .NET Framework version installed on the server.
Verification:
Adding the missing httpRuntime configuration immediately resolves TLS negotiation issues and enables successful license validation.