I tried moving photos and videos from my Android phone's internal storage to a 64GB SanDisk Extreme Pro microSD card using the built-in file manager. The first transfer, from a messaging app's media folders, only moved some files but those files still worked. I then moved the Camera folder into a subfolder inside Pictures. I used the phone briefly while the transfer was running, and the file manager did not show an error when it finished.
My phone's free storage increased from about 126GB to 105GB, so I assumed roughly 21GB had transferred successfully. However, the photos in the Camera folder no longer open, many videos are missing, and the files that remain show a size of 0 bytes. The Camera folder had previously contained around 116GB of data, while the card is only 64GB.
I immediately removed the card and have avoided using it except for recovery scans. Recuva found nothing useful. PhotoRec recovered some messaging-app files and a few camera photos, but the recovered videos are corrupted and cannot be played. The card came from a friend who said it was genuine and had worked reliably before. Is there anything else I can try to recover the videos?
2 Answers
The card could also be counterfeit, failing, or have less usable capacity than advertised, although that is not necessary to explain the problem here. A genuine 64GB card still cannot hold a roughly 116GB folder. Once a card reaches its limit, files can appear in the directory while containing no usable data.
Do not format the card, run repair tools, or save recovered files back onto it. Check the card’s real capacity later with a write/read test, but only after recovery is finished. If PhotoRec is finding only fragments and the original phone files were deleted, there may not be enough intact data left for the videos to be repaired.
Stop using both the card and the phone’s internal storage as much as possible. Since the Camera folder was much larger than the card’s capacity, the transfer could not have completed. A move operation may copy files and then delete the originals, leaving incomplete or zero-byte entries when the destination runs out of space.
The safest approach is to make a sector-by-sector image of the SD card first, using a tool such as GNU ddrescue, and run recovery software against the image rather than the original card. PhotoRec or similar tools may recover video fragments, but large videos are often difficult because they need their headers and data blocks intact. If the videos are especially important, stop experimenting and contact a professional data-recovery service.
The card is 64GB and the Camera folder was much larger than that, so I understand now why the transfer may have failed even though the file manager did not show an error. I’ll avoid writing anything else to the card.