摘要:The main scientific problems investigated in this article deal with technical evaluation of quality attributes of the main components of e‑Learning systems (referred here as DLEs — Digital Libraries of Educational Resources and Services), i.e., Learning Objects (LOs) and Virtual Learning Environments (VLEs). The main research object of the work is the effectiveness of methods of DLE components quality evaluation. The aim of the article is to analyse popular existing LO and VLE technical evaluation tools, and to formulate new more complex tools for technical quality evaluation of LOs and VLEs based on requirements for flexible DLE, as well as to evaluate most popular open source VLEs against new more complex criteria. Complex tools have been created for the evaluation of DLE components, based on a flexible approach. The authors have analysed existing tools for technical evaluation of LOs, and it was investigated that these tools have a number of limitations. Some of these tools do not examine different LO life cycle stages, and other insufficiently examine technical evaluation criteria before LO inclusion in the repository. All these tools insufficiently examine LOs reusability criteria. Therefore more complex LO technical evaluation tool is needed. It was investigated that this new more complex LO technical evaluation tool should include LO technical evaluation criteria suitable for different LO life cycle stages, including criteria before, during and after LO inclusion in the repository as well as LO reusability criteria. The authors have also examined several VLE technical evaluation tools suitable for flexible DLE, and it was investigated that these tools have a number of limitations. Several tools practically do not examine VLE adaptation capabilities criteria, and the other insufficiently examines general technical criteria. More complex VLE technical evaluation tool is needed. Therefore the authors have proposed an original more complex set of VLE technical evaluation criteria combining (1) General (Overall architecture and implementation; Interoperability; Internationalisation and Localisation; Accessibility) and (2) Adaptation (Adaptability; Personalisation; Extensibility and Adaptivity) VLE technical evaluation criteria. The authors have also selected and proposed to use the universal, clear and convenient DLE components' evaluation rating tool, and have evaluated three most popular open source VLEs against technical (both general and adaptation) criteria in conformity with this rating tool.