Sony FDR-AX40 How To Use Manual page 224

The maximum number of still image folders has been reached.
Cannot record still images.
You cannot create folders exceeding 999MSDCF. You cannot create or delete created
folders using this product.
Format the memory card, or delete folders using your computer.
This memory card may not be able to record or play movies.
This memory card may not be able to record or play images correctly.
Use a memory card recommended for this product.
Do not eject the memory card during writing. Data may be damaged.
Reinsert the memory card.
External media cannot execute functions.
Check the image database file by selecting
[Repair Img. DB F.]
If even then the indicator flashes, format the external media using your computer, and
then reconnect this product with the external media. Note that if you format the external
media device, all the recorded movies and photos in it are deleted.
If the same message still appears after formatting, the external media may not be
supported by this product, or it may be damaged. Try with another external media.
Unable to access external media.
Use the external media device in stable condition (the environment such as no vibration
and room temperature, etc.).
Make sure that the power source of the external media device is connected.
Others
Maximum number of images already selected.
You can select only 100 images at one time for:
Deleting movies/photos
Protecting movies/photos, or releasing the protection
Copying movies/photos
Data protected.
You tried to delete protected data. Release the protection of the data.
- [Setup] - [ Media Settings] -