Can no longer access Trendnet IP312W via Internet

[LarCrow]

I am away from my home for an extended period and for a month or so I was able to connect to my Trendnet camera via the net and get email from it whenever there was motion. Recently everything stopped working. I did have someone at home to unplug the camera and reboot it and now I get email photos from it whenever it senses motion but I still can't logon. That seems to indicate that my router is working OK but when I try to log on it will not complete. Windows Network Diagnostics says that my router IP is OK but that something is probably blocking my port assignment on my D-link router but I have no idea of what could have caused it to change or what I can do remotely to fix it.