Suddenly i couldn't install more apps, because "home" was full.

Using Storage Usage, I found out that I have a file;
"home/user/.sharing/outbox/attachment-IGC34U"

and it's size is 332.6 MB..

My draft and outbox folders are empty, and I can't find the file using the File Manager..

What can i do to regain space on my Home drive ?

Ok, It's fixed now.
I went to xterm, went root and typed
And now it's gone.
This blogpost , leads me to believe that it's something left over from a sharing account. Possibly i shared a video by accident.