When you are ready with an assembly and have signed it, you can version it. When you version an assembly, the current assembly and all the dependent assembly versions are maintained in the assembly manifest. When a versioned assembly is deployed into an environment, then that becomes the default version of your application and the system throws an assembly manifest mismatch error when either the current assembly or dependent assemblies do not match the default version. There is a way to override this using a configuration file, which tells the runtime to use a specific version instead of the default version.

When an assembly is executed at runtime, it performs multiple steps to resolve assembly binding:

1. It checks the current assembly for the version information and a unique name.
2. It checks for configuration files to see whether any version override policies are defined.
3. In the case of any policy changes, the runtime identifies and loads the redirected assembly as per the policy.
4. It checks the GAC, or the path specified in configuration files, then the application directory, subdirectories, and serves the assembly binding request.