No space left on device in spite partition is not 100% [duplicate]

I am trying to do the following on my Linux machine CentOS release 5.8

 cd /var/APPstoreldap/Home
 touch test
 touch: cannot touch `test': No space left on device

so I verified the partition disk space capacity in order to understand if /var/APPstoreldap/Home partition reached to 100%

But what I get is that partition is only 51%

 df -h | grep APPstoreldap

 /dev/mapper/vg07-var  5.0G  2.7G  2.0G  51% /var/APPstoreldap/Home

so please advice why I get

 No space left on device

What could be the problem here?

.

other test:

df -i| grep APPstoreldap

/dev/mapper/vg07-var  655360  655360       0  100% /var/APPstoreldap/Home

You have exhausted the number of inodes available in your filesystem. It's likely that you have a directory somewhere with a crap-ton of small files, hopefully some type of temporary files that can be deleted without issue. You'll need to find that directory and asses whether or not the files are critical.

Beyond that, you'll need to consider creating a new filesystem with a larger number of inodes and copying data over there.