Don't store the textbook. Store the vocabulary. The "Minna no Nihongo" Anki shared decks (updated 2021-2023) are high quality and include native speaker audio—something the PDF Drive scans never had.
Some public libraries (especially in the US and Canada) now offer digital rentals via Libby or Overdrive. In 2021, this was rare; today, you can find the Minna series digitally. Check your local library.
3A Corporation has started listing official e-books on Google Play. Search for "Minna no Nihongo Second Edition" (ensure the year is 2021). These are reflowable, searchable, and legal. minna no nihongo pdf drive 2021
While finding a PDF on Drive in 2021 felt like striking gold for many students, it came with significant downsides that often hindered progress:
To appreciate the keyword, you must understand the context. In 2021, Japan’s borders were largely closed to new students. Many international students who had paid for language school were stuck in their home countries. They needed digital access to their curriculum. Don't store the textbook
Simultaneously, self-learners exploded in number. With no access to physical bookstores selling Japanese imports, they turned to file-sharing.
Google Drive became the sharing platform of choice because: Thus, "minna no nihongo pdf drive 2021" became
Thus, "minna no nihongo pdf drive 2021" became a perfect storm of demand and access.