Not enough space in my R4 for a game?! Help please!

I downloaded Call of Duty: World at War off of Romulation, and then moved it to my R4...But it keeps saying: The disk in the destination drive is full.
Insert a new disk to continue.When I go to the Properties for COD: WAW, it says it takes up 61.3MB, and I've deleted several games and SAV files from my R4 that took up more than 64MB, but it still doesn't let me move it, repeating the same message (as I said before). Please help!(Yes, I've extracted the WINRAR file to get it out, I'm not new to downloading/extracting/playing them, it's just this one time it says it's full.)

try backing up your card and reformatting, it is presumably not recognising that you have deleted files.

Replying to #2

How do you back up the card and reformat it. so that it recognizes that I deleted files?

i dunno if this works for u or not but after you delete files try re- inserting the USB. it worked for me :)

Copy all your files somewhere. Connect MicroSD. And then go to My Computer, right click removable drive, go format.

Thanks, I got COD on the R4... But now there's a new problem!!!(BTW I'm not sure if I should start a new thread for this)When I try loading it, it says 'The save data could not be accessed. Please turn the power off and reinsert the DS card.'
I've already tried DragoDracini's suggestion to make it work, but it still isn't working :(
Should I try the same method again or is there another way to fix it?

Just update your firmware at http://www.linfoxdomain.com/ds/. Works fine with 1.18.