False Positive Validation on SD Card

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New member
Apr 5, 2024
I used ValiDrive ver_1.0.1 to test a 32GB SD card I bought online.
ValiDrive showed Declared size = 31.2 GB
ValiDrive showed Validated size = 31.2 GB
However Windows file explorer Properties say size is < 1 GB (0.99 GB)

There appears to be a flaw in ValiDrive ver_1.0.1 since it validates a Fake SD as being authentic in size.

ValiDrive 1 - False Positive Show 31_2 GB.jpg

Vali Drive 2 - win explorer say 1G.jpg

Validrive 3 - Version 1_0_1.jpg
Hi @Ram2300. In windows you are checking the size of the partition not the actual disk size. It could be that you only have a 1GB partition available.

Can you check via disk manager to see if there is any unused space that is not formatted or a drive with no drive letter that accounts for the missing space?

For example.
In Disk Management this drive shows 1GB formatted but 6.21GB unallocated

Drive properties shows only the 1GB for Drive G

Validrive knows theres 7.75GB total
Last edited:
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“What he said!”
(y) That was exactly what I was getting ready to say. In this case, it does look very much like you have a 1GB FAT partition on a 32GB physical drive. What does the drive say on its body? Does it also claim to be 32GB? If so, and given that ValiDrive would agree, that's what I would believe.

Also note that the properties you posted shows a FAT partition... not a FAT32. That means that it's a FAT16 partition whose maximum size of 4GB, not 32GB. So whatever it was that formatted that thumb drive, for some reason, chose to use a 16-bit FAT rather than a 32-bit FAT.