How do I get the file to overwrite rather than paste inside the existing file?

I want to clarify that the prompt to choose the replace my current data never comes

I just tried for about the twelfth time, and for some reason, this time the prompt to choose to replace my current data came up and I clicked yes and it worked, but I do not know why it worked this time but not before.

My guess is you have the folder that was to be overwritten open instead of the folder above it. However if you were using drag and drop it is just a little flaky at times about exactly where the "drop" happens. Especially in a folder tree where tolerances are small from one object (folder name) to the next.

Now that I moved my thunderbird from my lap top to my new computer, I am trying to copy the profiles folder from my old computer and paste it over the profiles folder in my lap top. I started by uninstalling thunderbird and deleting the profiles folder then rebooting so the new thunderbird is empty, but when I try to paste the old profile folder over the new one it either gets put next to or inside the new profile folder. Help!