Amazon Shipping Labels can not be created (Error : Sender (ForbiddenRequestBlocked)

Amazon Shipping Labels can not be created (Error : Sender (ForbiddenRequestBlocked)

When you create Amazon Shipping labels you may see

11:29:06 AmazonSC: Developer is blocked from making calls for the MWS section MerchantFulfillment as part of MWS Deprecation process [ForbiddenRequestBlocked:Sender]
11:29:07 225-6856478-83940950::Couriers::(Amazon Shipping) : Error : Sender (ForbiddenRequestBlocked)

Due to a change made by Amazon some customers will not be able to use One Stop Order Processing to create Amazon Shipping Labels.  You will either have to use your own MWS Developer/Authentication details (setup in Amazon Seller Central) or use Amazon Seller Central to manually create the Amazon Shipping labels.

This is a change made by Amazon, out of the control of One Stop Order Processing. No changes have been made to One Stop Order Processing and One Stop Order Processing will continue to create Amazon Shipping labels directly for some customers (who have their own Authentication/Developer Credentials.

NOTE : If you have your own MWS Developer Credentials you can get these from:

which will show you your Developer ID, under MWS credentials click on View to show your AWS Access Key ID and Secret Key (shown as Client secret). The AMWS Access Key ID and Secret Key are the values to enter in OSOP in the Amazon import custom settings