QUESTION I'm trying to copy a large file of 4.5GB on to the memory card in my Android phone, but it's not working. All other files seem to copy correctly, but this largest one is apparently too large for the card even though there's plenty of space left on it. Can you help?
HELPROOM ANSWER This problem is caused not by your memory card running out of space, but by a limitation on the maximum size of a file imposed by the FAT32 file system typically used when formatting memory cards.
You may find that copying the same large file works when using the phone's internal memory rather than the card, but if you want to use the card for files larger than 4GB it's going to have to use an alternative file system.
Microsoft's exFAT (Extended File Allocation Table) file system is designed with exactly this use in mind and can cope with a file size up to the theoretical maximum volume size of 144,100,000 Gigabytes.
The exFAT file system, which must be licenced from Microsoft, has been adopted by many, but not all, Android phones. If your phone supports the format you can format the card to exFAT on your PC using a card reader. The phone will then be able to store and read files larger than 4GB on the card.
The Samsung Galaxy SIII is an example of a phone which supports the exFAT file system as standard. The exFAT format is supported by versions of Windows starting with Windows XP and also by versions of Mac OS X starting with 10.6.5 and is therefore a good way to transfer large files between the two platforms.