lock symbol

[johannis]

preventing deletion of things?whats the meaning of lock or setting to fix or change lock

[attachment deleted by admin]

[ks-net]

this means that item is locked because it is either open this time for editing by an other user or it haven't closed-saved properly(usually of a browser back-hit)

you have to check-in items...
in top menu  administrator page >>system>>check  in