Cannot test store?

I tried to submit a test order in my store today using the 4111111111111111 credit card, however I received the following error:

(13) The merchant login ID or password is invalid or the account is inactive.

The login info in the payment module is username: testing, password: Test and the Transaction Mode is set to Test. I also get this error in pink at the top of my admin panel in the payment module:

CURL functions not found - required for Linkpoint API payment module

Even though I plan on signing up with authorize.net as I get closer to going live, I had thought I could test the store currently as I'm making changes, using the testing info already setup. Is this not the case? Can someone tell me what I'm doing wrong, or what needs to be done to submit a test order? Thanks!

If you do not have a valid account you cannot test a Payment module such as LinkPoint or AuthorizeNet ...

Ok, thanks. I thought that the username and password that were already entered were valid for testing purposes. After more research, I guess I'll just use the money order/check module for now.

You could use CC for credit cards as this is for manual credit cards and does not involve a gateway through Zen Cart ...

NOTE: when you pick a real gateway be sure to Remove it ...