[@Gene] Thanks for your thoughtful question, you’re absolutely right to be cautious.
The built-in Windows “hidden” attribute is quite limited. It only hides files visually, but they can still be accessed by many tools or even cause issues with some programs, as you experienced.
Vovsoft Hide Files works differently. It doesn’t just toggle visibility, it moves files to a protected location, renames them, and controls access via a password, making them effectively inaccessible without the app.
It can also optionally use encryption (SHA256/PKCS7), though that’s slower.
Regarding safety: the software includes a recovery mechanism, so you’re not easily “locked out”.
More details here:
https://vovsoft.com/blog/hide-files-faq/