file format

Yesterday, while doing a log and transfer of an MP4, I accidentally moved some files to my trash can, which caused the video to be corrupted. The video wasn't very important, but when i put the sandisk back in my GY-HM100U JVC Pro HD cam, I got errors saying the system file or something needed to be reset. I clicked ok and it said successful, but kept repeating the same error. So I put the disk in my mac and erased it using disk utility. I put it back in the camera and formatted it to record MP4's again. I was able to record and play back just fine, but when I put it into my mac, it doesn't recognize the format and gives me errors. Can anyone suggest what is happening?