I have just put together a Connection Manager VPN client (CMAK) and within it have specified the extra routing information that I needed. When I ran the client I got the following error message and could not find anything on the web with an answer, so here is the answer...
Error 1: Connect action to update your routing table failed (80070057) - shown in the VPN client
Error 2: ErrorCode = -2147024809 ErrorSource = to update your routing table - recorded in the VPN log file
The reason! It was because I had entered an incorrect routing record in the text file. So to get this right, add the routes manually when connected and make sure they work, and then duplicate these entries in the text file. If the routes cannot be added on the command line then the VPN connection will fail with the above error message.