In my custom application, written on NetOS 6.3, MCSendMail works well for most of my customers. Recently, however, Verizon customers with FIOS and an ActionTec MI-424-WR router are having problems. It seems the call to MCSendMail locks up and never returns. This, after calling MCSetSmtpAuthentication.
Replace the ActionTec router with a Linksys or D-Link and it works fine. Outlook, Eudora, etc all work fine with the ActionTec router. It's just the combo of ActionTec and the ConnectME that fails.
No other customers experience this. They have Verizon DSL on copper, Comcast, Qwest, Embarq, etc - all the usual ISPs, and they all work fine.
Anyone else observed similar issues? Has the email API in NetOS 7 changed significantly? Is there a chance it would fix the problem?