Since the last software update for mountain lion I am having a problem when moving screenshots to trash. Now a Finder box appears saying finder wants to make changes and I have to enter my password for every action.

Since the last software update for mountain lion, I am having a problem when trying to remove any screenshots to the trash. A box appears saying "Finder wants to make changes. Type your password to allow this"

I have checked Finder Preferences and cannot find any box that I can 'UNTICK' to resolve this. I sometimes take a lot of screenshots when I am researching something and now find I have to enter my password for every screenshot to be removed to trash.

Anyone got a solution please, Thanks