Are you certain that the issue started when you upgraded to 2018 rather than 2017?

Which dimension calculator are you using? Is this the same one that you had been using prior to experiencing any issues?



Unless you've always used the standard dimension calculator and worked around its limitations/inaccuracies, there is no reason to still use it. As for the differences, it is entirely too complicated to explain but suffice it to say that the old "Extended Dimensional Calculator" was very primitive in its calculations which often lead to wildly inaccurate estimates. The "Extended Boxing Dimension Calculator" is far more accurate, though as with any such algorithm, it is only an estimate and will never be perfect.

Even with the change, we are still having critical issues with USPS shipping options for our products, issues that we never had until making the switch to 2018. We are having to create false packaging dimensions for single products to allow for USPS shipping options to appear for orders with only one item. This is happening for both domestic and international shipping addresses.

OK, after considerable testing we've determined what's happening. Previous versions of BV Commerce did not properly handle package dimensions with USPS in all cases. We corrected those issues with BVC 2018 and are now sending correct package dimensions. What's happening now in your case is that USPS is not returning a rate for certain services. For example, they will not return a rate for International Padded Flat-Rate Envelope packages measuring 7" x 7" x 4". Unfortunately this is outside our control and is how their API is responding to correct data. It seems that they are treating this as a package that is too large to ship via that service, though there is no information on their website stating definitive max dimensions. They seem to follow the "if it fits it ships" rule, but their API does not. Presumably you've been able to ship a package with those dimensions, so it would seem that there is an issue with their API.

We have opened a support ticket with USPS about this, but honestly their track record is so abysmal that I do not expect any meaningful response.

Do you mean why isn't the method hidden when the rate is $0? If so, that's because you must be using a rules method. If you were using a USPS method directly it would never display. To hide a method when the rate is zero you can create a rule like this:

Here is the final response from USPS:



In other words, their API implements some type of limitation based on dimensions, but they do not define what the logic/limit is. It doesn't really matter what it is, though, because their API is making the determination on what dimensions are valid.

A developer could certainly pass bogus package dimensions that are known to be acceptable to their API, but that's really the only workaround.