I tested and confirmed the ShipStation connection.
On step 3 (Shipping Method) of checkout, the following error message is displayed and logged.
Misused header name, 'Content-Type'. Make sure request headers are used with HttpRequestMessage, response headers with HttpResponseMessage, and content headers with HttpContent objects.
Page URL: /checkout/OpcSaveBilling/
Solution:
I updated the GetRatesAsync method in ShipStationServices.cs (starting on line 263)
From this:
client.DefaultRequestHeaders.Add("Content-Type", CONTENT_TYPE);
var responseData = await client.PostAsync($"{API_URL}{LIST_RATES_CMD}", new StringContent(JsonConvert.SerializeObject(postData)));To this:
var httpContent = new StringContent(JsonConvert.SerializeObject(postData),Encoding.UTF8,CONTENT_TYPE);
var responseData = await client.PostAsync($"{API_URL}{LIST_RATES_CMD}", httpContent);
var data = await responseData.Content.ReadAsStringAsync();
That resolved the issue.
You can see my original post here:
https://www.nopcommerce.com/en/boards/topic/93165/nopcommerce-450-shipstation-error
Apologies for the double post. Originally, I wasn't sure if it was an actual bug or an error I made in configuration setup.
