NoSuchFieldError is a runtime error in Java that arises when an application tries to access or modify a field that no longer exists in a class, often due to incompatible changes made after compilation. This error does not need to be declared in a method's throws clause. It typically occurs when code is only partially recompiled, resulting in references to non-existent fields. For example, if a static variable is removed from a class and only the class is recompiled, any other class referencing the removed variable will trigger this error. To resolve NoSuchFieldError, developers should clean and recompile all files to ensure compatibility, use consistent versions of external JAR files, and utilize tools like Rollbar for real-time error tracking and management.