There were quite some fake memory cards spotted all around, especially those very cheap ones with massive capacities. There were also quite some problems on Bada Forums where several users had problems using large memory cards in Samsung Wave mobile phone. As it turns out, the memory cards were most probably either fake or defective. And best way to spot that is this tool, called H2testw made by Harald Bögeholz.
H2testw download (v1.4):
Just download the tool, select device to test and set it to test “all available space”. Tool will write data to the drive and later verify the content. If all the data returned is the same as it was written, the drive is good. But if returned data is not the same it can mean that either device is malfunctioning or it’s simply fake (that looks like 32GB, but is in fact only 1GB or even less) and it was just rewriting the data over and over. Was your problematic drive super cheap with massive capacity beyond anything you could get in a verified store? Now you know why.
Tool can verify all sorts of memory cards, USB drives, external or internal HDD drives.