Call to BizTalk web service does not start process
Then, after a while, when you call the web service nothing seems to happen.
you don't get any exception , but the process does not start nor can you see any errors in the event log or suspended instances in the BizTalk Admin console
Try and capture the SOAP body using the network sniffing tool of your choice and validate it against the schema.
Most chances you will find your request is invalid according to the published schema and the deserializaion failed (do you need to update the web reference?).
Wish Biztalk would be kind enough to report this error, but it doesn't.