SD cards locking up

After trying an update, the software kept saying i need to insert a SD card, although there was a high speed one in it. So i eventually bought a new card and updated. After a few tries the card got updated but got bricked. I tried a third card and it also bricked. It does download and install the update until a certain point but there is always one unreadable large file on the cards that can not be copied or deleted... So i have 3 bricked expensive SD cards and no solution from Garmin. I can read and write to the cards trough windows, but i can not delete files or format card. When trying to copy i get an error. 

SO the device can read/write, windows can read write but something goes wrong while writing to the SD card. Also Garmin express does not see the SD card although it is mounted in Windows.

No more ability to format card, this fails every time. 

I mailed Garmin but i had to reproduce the error... I'm not all that technical and already ruined 3 cards... and this makes my GPS not updable, so now newer maps makes the device unusable....