Currently Being ModeratedNov 14, 2012 4:06 AM (in response to giffyd)
Are you replacing the same app with an update? If so, delete the original, first.
Also, are you doing this logged in as an admin user?
If those two don't apply, open Disk Utility and Repair Disk Permisssions in the First Aid tab.
You can ignore most of the stuff dumped out, but make sure it finishes with permissions repaired.
Currently Being ModeratedNov 14, 2012 4:02 PM (in response to giffyd)
I am not updating the app, rather replacing it.
If it's any help I did some tests and I can't copy the .app from the dmg image to any other folder on my system.
Sorry, that's what I meant. If you don't own the app that is in there, you can't replace it with another. You have to first delete that app, then put the new one in. Odd, but that's the way it is.
Linc's already asked the questions for the second part.
Currently Being ModeratedNov 14, 2012 6:26 PM (in response to Linc Davis)
I happens with most of them (ever since I did the latest Mountaion Lion upgrate).
Essentially I can open the .dmg file and it creates the virtual disk. When I try to copy & paste from it to any other folder I get the error message.