Hello,I have to change the Color Setting in hundreds of blocks from "green" to "by layer".How can I do that easily /automaticly?your help is highly welcome. 

E.g. [CMD]SETBYLAYER[/CMD] ?

Another option shown here in post by "jay".http://forums.autodesk.com/t5/visual-lisp-autolisp-and-general/block-colour-change-for-lisp/td-p/1629195

Dear Vladimir,quick answer but not usefull, since I talk about hundreds of blocks and each one has to be opend.I will check the link from Connor.Regards