I'm installing nopcommerce to the wwwroot directory of my hosting account. My question is, there is a web.config file already present and it appears that the nopcommerce installation files have a web.config file as well. When I upload the nopcommerce installation files, it asks if i want to overwrite the original web.config file. What should I do?
You could save it to your hard drive if you are concerned about overwriting it. If you have never put anything in your wwwroot yet then the current web.config file is there by default and it probably would not hurt anything to overwrite it. Always be on the safe side and backup your data (the web.config file you want to overwrite).