I completed the online check in process for our upcoming Seascape cruise. Everything was in order and I was unable to down load the e ticket documents and received an error message every time saying I had not yet completed on line check in.
I called MSC, waited on hold for half an hour and then got a helpful agent who asked for my booking number. She looked it up, everything was complete. She then emailed the documents to me. Easy Peasy.
Yes, MSC's website is a train wreck.