This paper addresses one of the major web end-user software engineering (WEUSE) challenges, namely, how to verify and validate software products built using a life cycle enacted by end-user programmers. Few end-user development support tools implement an engineering life cycle adapted to the needs of end users. End users do not have the programming knowledge, training or experience to perform development tasks requiring creativity. Elsewhere we published a life cycle adapted to this challenge. With the support of a. wizard, end-user programmers follow this life cycle and develop rich Internet applications (RIA) to meet specific end-user requirements. However, end-user programmers regard verification and validation activities as being secondary or unnecessary for opportunistic programming tasks. Hence, although the solutions that they develop may satisfy specific requirements, it is impossible to guarantee the quality or the reusability of this software either for this user or for other developments by future end-user programmers. The challenge, then, is to find means of adopting a verification and validation workflow and adding verification and validation activities to the existing WEUSE life cycle. This should not involve users having to make substantial changes to the type of work that they do or to their priorities. In this paper, we set out a verification and validation life cycle supported by a wizard that walks the user through test case-based component, integration and acceptance testing. This wizard is well-aligned with WEUSE's characteristic informality, ambiguity and opportunisticity. Users applying this verification and validation process manage to find bugs and errors that they would otherwise be unable to identify. They also receive instructions for error correction. This assures that their composite applications are of better quality and can be reliably reused. We also report a user study in which users develop web software with and without a wizard to drive verification and validation. The aim of this user study is to confirm the applicability and effectiveness of our wizard in the verification and validation of a RIA. (C) 2016 Elsevier Inc. All rights reserved.