I have created a bitcoin.conf in the correct appdata location... With contents:
You will also have to allow incoming connections from your webserver, find in bitcoin.conf:
# By default, only RPC connections from localhost are allowed. Specify
# as many rpcallowip= settings as you like to allow connections from
# other hosts (and you may use * as a wildcard character):
add a line like:
You may want to make sure that actually nothing else but your webserver actually can
connect to your bitcoind, by adapting your firewall exception to only match connections from your webserver as well.
Also, i do not advocate such a setup, i'd rather run a bitcoind on a vps / locally on the webserver, and only use it for processing of payments. Do not actually store your valuable bitcoins there in larger amounts.