Originally Posted by mzayats
Fixed quite a lot of permissions inconsistencies, but didn't solve the applications folder issue...
Searching with Google and on Apple's support forums it seems a lot of people have this problem when they try to drag an app while one with the same name is already in the apps folder. Is that your case? Like if Skype is there you try to drag a newer version of Skype it gives the error? A work around seems to be to drag the original app to the trash first.
There are too many threads to read, but if your curious search. I just searched using, "The operation can't be completed, because you don't have permission to access some of the items"