Question: I'm recovering lost data off a hard drive using `ddrescue` and [How to Recover Data Even When Hard Drive is Damaged](http://www.geekyprojects.com/storage/how-to-recover-data-even-when-hard-drive-is-damaged/)  

I've got all the data transferred to my destination drive and so now its time to restore the new raw image. 

My problem is when I go to unmount the drive it says the device is busy. What am I missing? Please help.

Answer: 
Reading through that guide, `/dev/sda` is mounted at `mnt`, and you are still in directory `mnt/recovery` at the point you try to unmount it. 

You can't umount it because you are still using it, so change directory first:- 

```
cd ~

```

and then 

```
sudo umount /dev/sda 

```

and it should unmount. If not, edit your question to include what happened.
You could try:

```
sudo umount -l /mountpoint/of/your/partition

```

`-l` forces the partition to unmount even if it is in use / busy.