This problem began with an attempt to provide additional storage for my android tablet, but it now extends to questions about the reader's use on my two Win 7-64b computers, a desktop and a laptop.
My tablet is a Samsung Galaxy Tab 10.1, and it has no USB port or card reader. I have a Samsung USB connection device which plugs into the tablet and provides a USB port on the opposite side. This allows the use of a USB thumb drive, and it works with no problem. I'd seen many USB card readers advertised, and I decided on the SanDisk MicroMate (a SDHC device), thinking I could connect this to my tab and quickly have additional (using a new 8GB SDHC card) storage for reading and writing. When the connection was made, however, the message was "Blank USB storage; USB storage blank or has unsupported format" I offer this to indicate that the reader does seem operational, but the card cannot be accessed using the tab's file managers, In trying to figure out the problem, I found strange disparities with my Windows PCs:
1. If I insert the card into the internal card reader of either of my computers, it is immediately accessible, and I was able to copy a file to it. Format is FAT32.
2. If I connect the reader to a powered USB port on either computer, the device shows no errors in Device Manager, but when the card is inserted into the reader, the error "the drive must be formatted" appears. I also tried using the 1 GB card from my camera with the same results.
Can anyone help me figure this out?