Issues loading files

I was recently trying to load some pictures to Mylio from the Camera Roll file on my laptop. This file contains some pictures taken on my wife’s ipad and therefore, were heic files.
None of the heic pictures loaded OK but Mylio left blank spaces, with either an i in the frame or an i with a page icon, I think. On reading reading the tutorial notes I found that Mylio could not handle heic files. I then found an app that converted heic to jpg. When this was finished Mylio only shown some of the pictures I had converted and for these files I deleted the heic originals. Now I have jpg files on my laptop which Mylio cannot apparently identify (although the converted files are fully functional in all other respects) and to my astonishment it reloaded all the deleted heic picture files leaving me totally bemused as to what was happening. Can anybody enlighten me?

I assume your laptop is running Windows? Mylio depends on having operating system support to decode HEIC files. Apple devices of course already have this support. If you don’t already have this on your Windows 10 machine, you’ll need to install the free HEIF and/or HEVC extensions from the Microsoft Store.

As for deleted files re-appearing, did you delete these from within Mylio? Or just from the file system? If the latter, then it’s probably from Mylio protecting against accidental deletions with this setting:

Settings -> Source Folders -> Safe Delete on Vaults [X]