USPS Module is not working

[renaissancefarms]

Hello.  I am new to Prestashop.  I am building a new store on a demo site before I replace our existing ZenCart store.  I cannot get the USPS shipping module to work!  I have been through all the related forum posts and have try everything I can think of.  I still get an error on checkout "There are no carriers that deliver to the address you selected."

 

I am using Prestashop v1.6.0.9 and Connect to USPS v1.3.5.

 

Can anyone offer some advise?  I have uninstalled and reinstalled the module a few times and nothing seems to be working.  I must be missing something simple.

 

Thanks

[renaissancefarms]

I should have noted that I get "Connect to USPS is configured and online!" in the module settings, but still can't get access rate informaiton in the shopping cart.

 

Thanks

[renaissancefarms]

Well - I saw someone else had turned off 1-page checkout and got it to work.  I already had it off so I just turned it on to see what would happen.  Presto! now it works.  I can turn it back off and it still works.  No idea why it's happening, but good luck to the next person.

[renaissancefarms]

After installing the paypal module, the usps module stopped working again.  Turning off one page checkout no longer helps.  Anyone know how to get this thing to work consistently??