no acces to files \ read permission denied

[werbungHCFB5]

cant get acces to some Files,

the last used Files i can edit, but everything that is older then 30days... no option. I cant even make a right click on it.

-> it shows me 7/10 in use but there are only 6, and the Screw i cant delete, cause it shows the Error " is in an Project"