Having filled all the required fields with valid data and clicking "Connect", your FedEx business account will be connected to the Calcurates account.
In the carriers grid the FedEx carrier label will be changed (from red to green "connected" icon):
Popular Connection Issues
Invalid Billing Address
After clicking "Connect" you may get the following error:

A shipping carrier error occurred: Unable to complete FedEx registration. Invalid Billing Address.
When connecting your FedEx account, make sure you are specifying the Shipping Address listed in your FedEx account, not a separate billing address.
Where do you find the FedEx Shipping Address?
Log in to your FedEx account and click on your profile name. Then go to Administrative Tools > FedEx Accounts and click on your account number. The FedEx Shipping Address will be listed on this page.