Cannot write modification time to my phone's SDXC card

[bezzerkk]

So, I have all my music files - currently around 16000 files - on a my local LAN's Linux server and wish to sync them all to my new mobile phone's 256GB SDXC card.
For syncing I use the latest Freefilesync v14.3 installed on my Windows 10 PC that is also connected to my LAN. I compare using "File time and size" and then synchronize using "Mirror". The phone(s) is connected to my Windows PC using a USB-c cable.

With my former old phone - a Xiaomi MiA1 Android v9+Aug 2020 security update (internal storage formatted as EXT4FS with 4kB blocks) having a 128 GB Kingston Canvas Go1 Plus SDXC card (came formatted as VFAT/FAT32 with 32kB blocks) - there is/was no problem syncing.

But alas with my new phone, a Samsung Galaxy A16 LTE/4G 8GB/256GB with Android v15+May security update (internal storage formatted as F2FS with 4kB blocks) I'm flooded with get the dreaded warnings:

Cannot write modification time of "mtp:\\Galaxy A16\SD card\Music\........ .ffs_tmp"

whether I write to the SD card's EXFAT area or to its internal 256GB F2FS storage.

Now, my newly bought Kingston Canvas Select Plus SDXC 256GB card came formatted as EXFAT. So I now wonder if reformatting the card to instead using the old FAT32 then maybe Freefilesync updating file modification times would work again. Though to try this I first need to buy a SD card reader but before I'll do that I try asking the esteemed forum members on their views and opinions on the matter. Has anyone got file syncing working using a **FAT32** SD card?

Regards,
Bezzerkk

[John1234]

Hi,

Files by Google and format your SD card into fat32 or exfat for your testing purposes

📦 Play Store: Preinstalled or search “Files by Google”

⚙️ Format: Only reformats to internal-compatible formats (usually FAT32 or exFAT)

👤 Root Required: ❌ No

🛠 You can use it to erase and format SD cards for portable or internal storage.

📍 Go to: Settings > Storage > SD card > Format

[bezzerkk]

Thanks - I downloaded "Files by Google" and formatted my SD card. There is however no option to choose between SDFAT (=FAT32 ?!) or EXFAT before formatting. Seems though it always (?) chooses SDFAT by default.

However SDFAT did unfortunately not help as I still get the "write modification time" warnings.

So, seems I have no choice but to compare to "File size" instead... :-(

EDIT: SDFAT is a library that supports FAT16, FAT32, and exFAT file systems on Standard SD, SDHC, and SDXC cards.
=> Means I don't know if my card now is formatted as FAT32 or EXFAT!!

[John1234]

Hi,

On Android, when you format an SD card using the system settings, the default file system format used depends on:

1. Card size

≤ 32 GB: Formatted as FAT32

> 32 GB: Formatted as exFAT


Sorry it didn't help. I have no other suggestions at this point.

[xCSxXenon]

For what it's worth, I've had to use File Size with my Samsung phone for YEARS now. Must be how Samsung or newer Android versions handle the protocol

[bezzerkk]

The only way for me to have a FAT32 formatted card is buying a card reader and connect it to either a Windows PC or Linux PC. Now Windows generally doesn't allow formatting large SD cards to FAT32 directly, so we need to use a third-party tool like FAT32 Format or Rufus. Using a Linux machine one could of course use mkfs.vfat

However it seems unlikely that even with a FAT32 formatted SDXC card the file modification warnings would go away.

NOTE: FAT32 has a 4GB file size limit, so it might not be suitable for all uses.