Lazaclip

Sony A6700 RSV file: what to do when a video didn't save

Updated 3 November 2026

The A6700 is a hybrid camera: many people switch between photos and video all day. A typical way to end up with an .RSV file is a busy moment: the battery hits zero during a clip, or the card comes out to copy photos while a video was still being written. On the card you then find something like C0118.RSV next to the finished clips, and nothing opens it.

What the .RSV file is

The camera writes a video into an .RSV working file while recording, and turns it into an .MP4 when you stop: it adds the index that tells players where every frame and every block of sound is, and renames the file. An interruption skips that step. The footage is usually still there, but without the index nothing can play it. The longer version is in What is an RSV file?

The A6700 records XAVC S and XAVC HS (and, depending on settings, XAVC S-I) as .MP4, so an interrupted clip in any of these formats leaves this kind of file.

One card slot means one copy

The A6700 has a single SD card slot. Unlike cameras with two slots, there is no second card that might hold a complete copy of the take. The .RSV on this card is the only one, which makes the next steps matter more.

What not to do

  • Don't format the card, even if the camera asks you to.
  • Don't keep shooting on it, photos included. New photos and videos can land in the space where the interrupted recording sits. Use another card for the rest of the day.
  • Don't delete the .RSV to "clean up" the card.
  • Don't import with software that skips unknown files. Some import tools only copy photos and finished videos. Copy the folders by hand instead.

Copy the card the right way

Put the card in an SD card reader and open it in File Explorer. Photos are in DCIM; videos are in a separate folder, PRIVATE/M4ROOT/CLIP. Copy the whole PRIVATE folder to your PC. If you only copied DCIM, you don't have the video at all, which is a common reason people think the clip is lost.

The free first try

Some Sony cameras try to recover an interrupted clip on their own when you put the card back into the same camera with a charged battery. We can't promise the A6700 will do it for your clip, but it costs nothing once you have a copy:

  1. Charge the battery.
  2. Put the same card back into the same A6700.
  3. Switch on and wait. If you see a message about recovering data, let it finish.
  4. Check PRIVATE/M4ROOT/CLIP again for an .MP4 with the same number.

Rebuilding the video on Windows

If the .RSV is still there, the index has to be rebuilt. Lazaclip is our program for Windows 10 and 11 that does this (we make it, so this part comes from the seller). It runs on your PC, uploads nothing and opens the .RSV read-only:

  1. Open the card or the copied folder. The program finds every .RSV in PRIVATE/M4ROOT/CLIP and checks each one.
  2. Watch the free Preview 10 s, with a trial watermark, in your video player.
  3. With a license, save the full .MP4 to a folder on your PC.

Your video and sound are copied as recorded, without re-encoding. The repaired file goes to your computer, never back onto the card.

Has it been tested with the A6700?

Not yet. We tested Lazaclip on A7S III recordings in XAVC S (8-bit and 10-bit), XAVC S-I and XAVC HS, all rebuilt without a reference clip, with frames and audio identical to the original up to the last unfinished group of frames. We also tested an older camera, the original a7S, where a healthy clip from the same card is picked automatically as a reference. The A6700 uses the same XAVC S / XAVC HS recording format; the free preview shows whether the program can read your file before you pay.

Keep a few healthy clips on the card that were recorded in the same mode. If a reference turns out to be needed for your file, the program looks for one on the same card.

What to expect

  • The last second or so before the interruption is lost: that part was never completely written.
  • If you shot more photos or videos on the card afterwards, part of the file may have been overwritten.
  • An XAVC HS clip needs a player or editor with H.265 support. In Windows' built-in apps that can mean Microsoft's HEVC video extension.

Avoiding it

  • Check the battery level before you start a long clip, and carry a spare.
  • Before you take the card out, stop recording and give the camera a moment to finish writing.
  • If you copy photos during the day, switch the camera off first, then remove the card.
  • A second card in your bag lets you keep the problem card untouched until you get home.

Using a smaller Sony body for vlogging? See the ZV-E10 II guide. A compact full-frame? The A7C II guide.