exFAT formated SDHC card in a USB Mem adapter only recognised sometime

I'm not 100% sure if this is a hardware or software question but since it revolves around hardware I thought this forum might be most appropriate.

I have various Windows 7 systems and I have just acquired a 64GB SDHC micro memory card. This card came formatted as exFAT. If I put this card in the memory card slot in one of these systems using a Kingston SDHC Micro adapter it is recognised and I can process any video files on it perfectly. However if I place the SDHC card in an Integral (makers name) USB memory adapter, and the Kingston micro SDHC adapter then the same system does not recognise the card and says I need to format it (it shows zero bytes available on the card as well). Can anyone tell me if this is a normal situation and there is perhaps a 'hardware' limitation with USB 2 ports and USB Memory card adapters? or possibly this is a software issue? Just for clarification the SDHC micro card (Samsung EVO) in question is used in a Garmin VIRB camera for taking videos of bike rides and works perfectly well in the camera.

In one of my other systems I see the same results when using the USB memory card adapter, but I cannot try an SDHC card slot because I do not have a spare one in this other system.

Thanks for your help.
Bernard

Hi Pauly,

Thanks for the feedback. I thought the Kingston Micro adapter was purely a piece of hardware that downsized/upsized the physical connectors and wouldn't have any influence on how Windows 7 saw the card, but I could be wrong.

Do you think its possible the USB 2 port or possibly the actual USB card adapter has some limitation in terms of software support - I though that might be a more likely cause but I have no evidence to support it despite quite a bit of browsing on the web? There are no warnings as far as I can see about limitations on how you attach these memory cards to a Windows 7 system.
regards, Bernard

Ops, I need to edit my original post, I just discovered the card is an SDXC rather than SDHC one (the printing on it is minute - I need a magnifying glass to read it) - the Integral adapter says it is SDHC, so I guess its possible that may be the problem - I've ordered an SDXC USB adapter to check that out.
Bernard

It looks like I've solved my problem. The new SDXC memory card adapter allows my systems to recognize the memory card for what it is. It seems it is important to have an SDXC adapter for and SDXC card and an SDHC adapter will not do. Plugging the new adapter into the PC caused some new drivers to be loaded and then it all worked. So mystery explained. Thanks to Pauly for raising the possibility, also to my magnifying glass for allowing me to read the SDXC label on the card - it must be in 2 point font!