When I have over 100 emails to delete and I don't want to open them. I can only delete them
one by one...isn't there a way to just click on all (or those I choose to delete) and delete at once?
Click on the checkbox to the left of the first message, then hold down the Shift key and scroll down to the last message in the block you want to delete and mark the checkbox for that one. This will "select" everything in between. Then hit the Delete icon in the toolbar. Or you can check as many individual messages as you like and Delete those. Either way, using the checkbox will not open any of them.