I inserted an sd card but my galaxy tablet 2 don't recognise it.

It sounds like the tablet is having trouble reading your 128 GB SD cards.
There are a few things you can try to troubleshoot this issue:

1. Check the SD card for any visible damage. If the card is physically damaged, it may not work correctly.
2. Make sure that the SD card is properly inserted into the SD card slot on the tablet. It should fit snugly and be fully inserted.
3. Check that the SD card is compatible with your tablet. Some tablets can only support SD cards up to a certain capacity or with a certain type of file system.
4. If the SD card was working fine before and has suddenly stopped working, it's possible that the card has become corrupt. In this case, you may need to format the card to fix the issue.
5. If none of these steps help, you may need to try a different SD card to see if the issue is with the tablet or the SD card.

It should automatically recognise it. Reboot and check. Check with another memory card. if still does not work then mostly the connector on the tablet has gone bad

Hi Samsung recommends a class 6 card (6MBps) write speed minimum for there flagship devices CHECK THE SPEED OF YOURE CARD .have a look on SD card fora number from 2 to 10MBps check the size of you're sd card maximum size is 32 GB Cheers

3 types of SD card, Large, Medium, & Mico Card. SD card is pushed into slot on the side of the Tablet, then left in. Various Capicity1 Gig 2 Gig 12 Gig 32 Gig , 64 Gig. I suggest you take Tablet to nearest Comuter Store, they will sort out what you need & require

reset it without the sd card installed.
also...if you have a card reader on your computer....put the sd card in it and see if there is anything on the card. You may have deleted everything on the card by reseting your tablet with the card in it.

2 things can be happening.
1. the card is one that's not dependable like the chinese ones that cost $5 it can become corrupt easily.
2. You need to do a full format of the card and that should take care of it.

It depends on how it is formatted in the first place. The tablet will only recognise the first partition.

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