Hey Guys, I have had my Simple Drive 500GB External Hard Drive for some time now but I have noticed recently that whenever I delete a file from it the hard drive doesn't give the space back 
. For Example: I Have 143.95GB on the External Hard Drive free but when I delete a 20gig file it doesn't give the space back on the External Hard Drive, it stays at 143.95GB. Also, this happens with many of my flash drives etc. So do any of you guys know how to fix this. Thanks and any answers are greatly appreciated. (BTW I Don't Want to reformat the External Hard Drive) Also the External HD is already in Mac OS Extended Journaled Format
. For Example: I Have 143.95GB on the External Hard Drive free but when I delete a 20gig file it doesn't give the space back on the External Hard Drive, it stays at 143.95GB. Also, this happens with many of my flash drives etc. So do any of you guys know how to fix this. Thanks and any answers are greatly appreciated. (BTW I Don't Want to reformat the External Hard Drive) Also the External HD is already in Mac OS Extended Journaled Format 