My brother told me two weeks ago that some of his files were missing and last week all of his files disappeared (together with some installed programs). The weird thing is that the folder structures are still there - it is just the files in the folders that are missing.
It seems that I can recover the non-backed-up files with photoRec (of testDisk), but would like to know what can cause this and how do I prevent it from happening in the future?
P.S We did clean the computer with an air blower right before all the files disappeared, but I doubt that this can cause it seeing that some disappeared before then and the computer only has xUbuntu 13.04 on it.
EDIT I forgot to mention that all configs were also reset (launcher(s) settings and background, including email accounts).