New wildfire owner here. I don
I have the same problems and have had to send back the cheap SD card I brought on ebay
You can format the sd card, try that. Go to settings > SD & Phone Storage >Format SD Card
You might also want to unmount it and then re-mount it
The only view on the SD Card that is built into the phone as standard is from menu, settings, SD & phone settings... this will tell you the space on the card and the available space. (for example my 8GB card says Total 7.40 GB and 2.76GB free space)
To see the files on the SD card you can plug the phone into your computer with the USB cable and choose the disk option.
Or you can download an explorer app from the market. there are a few good ones. I use ES File Explorer, others on here use AndroXplorer or Astro.
Thank you both for your replies. It was just that information I needed. Now I finally can access my sd card.
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