: Users have reported that inserting a new card into a phone (such as UMIDIGI or budget brands) results in the phone "rediscovering" the card as a 2GB volume containing abcd.iso , wiping all previous music and videos.
Is it a virus (gone wrong)? - Android Community - Google Help abcd.iso sd card
Think of an abcd.iso file as a digital snapshot of an entire physical disc (like a CD, DVD, or Blu-ray). It contains not just the files, but the file system structure and the boot information required to start a computer or device. : Users have reported that inserting a new