To delete it, make sure that if you're using a microSD to SD adapter, the lock switch is un the UNLOCKED position (typically closest to the contacts).
To extract it, try extracting to your desktop or another folder first, then try moving the folder to the SD. Again, if your memory card is locked, you won't be able to do that.
If you're not using an adapter, the microSD might be stuffed. My best friend gave me a 16GB microSD that suffered water damage - the card is still readable, but shows as locked, regardless of whether I use a microSD to SD adapter or a microSD reader.
Edit - also, on the card, right click the __aio folder and akmenu4.nds file and make sure that the read only attribute is unchecked for both of them (not checked and not with a square in it)
Edit 2 - ^ if it is, uncheck it, when it asks if you want to apply it only to the current folder or all files and subfolders, choose the all files and subfolders one (or whatever the nearest match to that is)